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KS3 SCIENCE - KS3 BIOLOGY QUIZZES

KS3 BIOLOGY QUIZZES

Doc B's revising for KS3 SCIENCE  Doc Brown's KS3 BIOLOGY

I appreciate SAT levels have gone, but I hope these KS3 biology Quizzes will still be of some use. Although I've already produced some combined KS3 biology quizzes, I welcome suggestions from teachers so I may produce useful compilation KS3 biology quizzes suitable for any school doing KS3 biology and any KS3 biology scheme of work now that the KS3 biology levels and KS3 biology SAT exams have gone.

Copying of the KS3 biology quizzes is NOT permitted but you can printout the KS3 biology questions to use in class or for homework.

The first part of the page is the most important - the links to the KS3 Biology multiple choice quizzes.

The rest of the page is lots of guidance for doc b to help design the most useful KS3 Biology quizzes


For after KS3 SCIENCE ...

GCSE 9-1 Chemistry Notes * GCSE 9-1 Biology Notes * GCSE 9-1 Physics Notes



The KS3 Biology Multiple Choice Questions

The KS3 Biology Questions are selected at random from big databases.

PLEASE NOTE: (1) <= back on the link bar of the quiz returns you to the previous web page.

(2) Don't use the usual refresh button on the upper browser to repeat the quiz, use the    REPEAT QUIZ - fresh Q's    on the quiz link bar.

(3) A small proportion questions are deliberately very challenging and more like GCSE level, but only the odd one! and most cover the full range of ability of KS3 science students.


10 Q multiple choice question KS3 Science-BIOLOGY quizzes

  1. KS3 Biology Quiz - 7AQUIZ 7A on "Cells" Questions on types of plant and animal cells, idea of plant and animal organs, functions of cells

  2. KS3 Biology Quiz - 7B ReproductionQUIZ 7B on "Reproduction" Questions on human reproductive organs, sperm/egg cells, fertilisation, menstrual cycle, pregnancy, birth

  3. KS3 Biology Quiz - 7C Environment & feeding relationshipsQUIZ 7C on "Environment & feeding relationships" Questions on different environments and habitats, food chains, adaptations

  4. KS3 Biology Quiz - 7D Variation and classificationQUIZ 7D on "Variation and classification" Questions on classification/differences - plants, animals, vertebrates and invertebrates

  5. KS3 Biology Quiz - 8A Food and digestionQUIZ 8A on "Food and digestion" Questions on the importance of food, types of food in a balanced diet, the digestive system, action of acid/alkali/enzymes in breaking down food

  6. KS3 Biology Quiz - 8B RespirationQUIZ 8B on "Respiration" Questions on link between digestion and respiration, chemistry of respiration, transport of substances involved in respiration, function of the lungs

  7. KS3 Biology Quiz - 8C Microbes and diseasesQUIZ 8C on "Microbes and diseases" Questions on micro-organisms, function of yeast, causes of disease, prevention/cure of disease, the bodies defence systems, medicines and immunisation

  8. KS3 Biology Quiz - 8D Ecological relationshipsQUIZ 8D on "Ecological relationships" Questions on food webs, population changes e.g. predator-prey relationship, pyramid of numbers

  9. KS3 Biology Quiz - 9A Inheritance and selectionQUIZ 9A on "Inheritance and selection" Questions on inherited characteristics, effect of environment on characteristics, variation in offspring, selective breeding for particular character, cloning

  10. KS3 Biology Quiz - 9B Fit and healthyQUIZ 9B on "Fit and healthy" Questions on the respiratory system, respiration chemistry, fitness levels, importance of diet, effects of drugs and alcohol, how healthy are we?

  11. KS3 Biology Quiz - 9C Plants and photosynthesisQUIZ 9C on "Plants and photosynthesis" Questions on function of the parts of plants, how they grow, role of leaves and photosynthesis chemistry, environmental importance of plants

  12. KS3 Biology Quiz - 9D Plants for foodQUIZ 9D on "Plants for food" Questions on food sources, uses of fertilisers and pesticides, competition for resources between plants, what are the best growing conditions for plants?



SEE ALSO the KS3 Science Quiz compilations

20 Q m/c QUIZ on  ORGANISMS, BEHAVIOUR and HEALTH

20 Q multiple choice QUIZ on CHEMICAL, MATERIAL BEHAVIOUR

20 Q multiple choice QUIZ on ENERGY, ELECTRICITY, FORCES

20 Q multiple choice QUIZ on ENVIRONMENT, EARTH, UNIVERSE


National Curriculum KS3 Science BIOLOGY specification

Subject content – KS3 Biology Pupils should be taught about:

KS3 biology Structure and function of living organisms

KS3 biology Cells and organisation     (National Curriculum KS3 science-biology)

cells as the fundamental unit of living organisms, including how to observe, interpret and record cell structure using a light microscope

the functions of the cell wall, cell membrane, cytoplasm, nucleus, vacuole, mitochondria and chloroplasts,

the similarities and differences between plant and animal cells,

the role of diffusion in the movement of materials in and between cells

the structural adaptations of some unicellular organisms

the hierarchical organisation of multicellular organisms: from cells to tissues to organs to systems to organisms.

KS3 biology The skeletal and muscular systems     (National Curriculum KS3 science-biology)

the structure and functions of the human skeleton, to include support, protection, movement and making blood cells

biomechanics – the interaction between skeleton and muscles, including the measurement of force exerted by different muscles

the function of muscles and examples of antagonistic muscles.

KS3 biology Nutrition and digestion      (National Curriculum KS3 science-biology)

content of a healthy human diet: carbohydrates, lipids (fats and oils), proteins, vitamins, minerals, dietary fibre and water, and why each is needed

calculations of energy requirements in a healthy daily diet

the consequences of imbalances in the diet, including obesity, starvation and deficiency diseases

the tissues and organs of the human digestive system, including adaptations to function and how the digestive system digests food (enzymes simply as biological catalysts)

the importance of bacteria in the human digestive system

plants making carbohydrates in their leaves by photosynthesis and gaining mineral nutrients and water from the soil via their roots.

KS3 biology Gas exchange systems      (National Curriculum KS3 science-biology)

the structure and functions of the gas exchange system in humans, including adaptations to function

the mechanism of breathing to move air in and out of the lungs, using a pressure model to explain the movement of gases, including simple measurements of lung volume

the impact of exercise, asthma and smoking on the human gas exchange system

the role of leaf stomata in gas exchange in plants.

KS3 biology Reproduction      (National Curriculum KS3 science-biology)

reproduction in humans (as an example of a mammal), including the structure and function of the male and female reproductive systems, menstrual cycle (without details of hormones), gametes, fertilisation, gestation and birth, to include the effect of maternal lifestyle on the foetus through the placenta

reproduction in plants, including flower structure, wind and insect pollination, fertilisation, seed and fruit formation and dispersal, including quantitative investigation of some dispersal mechanisms.

KS3 biology Health      (National Curriculum KS3 science-biology)

the effects of recreational drugs (including substance misuse) on behaviour, health and life processes.
Material cycles and energy

KS3 biology Photosynthesis       (National Curriculum KS3 science-biology)

the reactants in, and products of, photosynthesis, and a word summary for photosynthesis

the dependence of almost all life on Earth on the ability of photosynthetic organisms, such as plants and algae, to use sunlight in photosynthesis to build organic molecules that are an essential energy store and to maintain levels of oxygen and carbon dioxide in the atmosphere

the adaptations of leaves for photosynthesis.

KS3 biology Cellular respiration     (National Curriculum KS3 science-biology)

aerobic and anaerobic respiration in living organisms, including the breakdown of organic molecules to enable all the other chemical processes necessary for life

a word summary for aerobic respiration

the process of anaerobic respiration in humans and micro-organisms, including fermentation, and a word summary for anaerobic respiration

the differences between aerobic and anaerobic respiration in terms of the reactants, the products formed and the implications for the organism.

KS3 biology Interactions and interdependencies      (National Curriculum KS3 science-biology)

KS3 biology Relationships in an ecosystem     (National Curriculum KS3 science-biology)

the interdependence of organisms in an ecosystem, including food webs and insect pollinated crops

the importance of plant reproduction through insect pollination in human food security

how organisms affect, and are affected by, their environment, including the accumulation of toxic materials.

KS3 biology Genetics and evolution      (National Curriculum KS3 science-biology)

KS3 biology Inheritance, chromosomes, DNA and genes     (National Curriculum KS3 science-biology)

heredity as the process by which genetic information is transmitted from one generation to the next

a simple model of chromosomes, genes and DNA in heredity, including the part played by Watson, Crick, Wilkins and Franklin in the development of the DNA mode

differences between species

the variation between individuals within a species being continuous or discontinuous, to include measurement and graphical representation of variation

the variation between species and between individuals of the same species means some organisms compete more successfully, which can drive natural selection

changes in the environment may leave individuals within a species, and some entire species, less well adapted to compete successfully and reproduce, which in turn may lead to extinction

the importance of maintaining biodiversity and the use of gene banks to preserve hereditary material.
 



AQA KS3 Science BIOLOGY specification

Subject content – KS3 Biology Pupils should be taught about:

AQA KS3 biology 3.8 Organisms

AQA KS3 biology 3.8.1 Movement

Explore how the skeletal system and muscular system in a chicken wing work together to cause movement

AQA KS3 biology Know

The parts of the human skeleton work as a system for support, protection, movement and the production of new blood cells.

Antagonistic pairs of muscles create movement when one contracts and the other relaxes.

Keywords

Joints: Places where bones meet.

Bone marrow: Tissue found inside some bones where new blood cells are made.

Ligaments: Connect bones in joints.

Tendons: Connect muscles to bones.

Cartilage: Smooth tissue found at the end of bones, which reduces friction between them.

Antagonistic muscle pair: Muscles working in unison to create movement.

AQA KS3 biology Apply

Explain how a physical property of part of the skeleton relates to its function.

Explain why some organs contain muscle tissue.

Explain how antagonistic muscles produce movement around a joint.

Use a diagram to predict the result of a muscle contraction or relaxation.

AQA KS3 biology Extend

Predict the consequences of damage to a joint, bone or muscle.

Suggest factors that affect the force exerted by different muscles.

Consider the benefits and risks of a technology for improving human movement.
 

 

AQA KS3 biology 3.8.2 Cells

AQA KS3 biology Identify the principal features of a cheek cell and describe their functions

AQA KS3 biology Know

Multicellular organisms are composed of cells which are organised into tissues, organs and systems to carry out life processes.

There are many types of cell.

Each has a different structure or feature so it can do a specific job.

Skill Use a light microscope to observe and draw cells.

Facts

Both plant and animal cells have a cell membrane, nucleus, cytoplasm and mitochondria.

Plant cells also have a cell wall, chloroplasts and usually a permanent vacuole.

Keywords Cell:

The unit of a living organism, contains parts to carry out life processes.

Uni-cellular: Living things made up of one cell.

Multi-cellular: Living things made up of many types of cell.

Tissue: Group of cells of one type.

Organ: Group of different tissues working together to carry out a job.

Diffusion: One way for substances to move into and out of cells.

Structural adaptations: Special features to help a cell carry out its functions.

Cell membrane: Surrounds the cell and controls movement of substances in and out.

Nucleus: Contains genetic material (DNA) which controls the cell’s activities.

Vacuole: Area in a cell that contains liquid, and can be used by plants to keep the cell rigid and store substances.

Mitochondria: Part of the cell where energy is released from food molecules.

Cell wall: Strengthens the cell. In plant cells it is made of cellulose.

Chloroplast: Absorbs light energy so the plant can make food.

Cytoplasm: Jelly-like substance where most chemical processes happen.

Immune system: Protects the body against infections.

Reproductive system: Produces sperm and eggs, and is where the foetus develops.

Digestive system: Breaks down and then absorbs food molecules.

Circulatory system: Transports substances around the body.

Respiratory system: Replaces oxygen and removes carbon dioxide from blood.

Muscular skeletal system: Muscles and bones working together to cause movement and support the body.

AQA KS3 biology Apply

Explain why multi-cellular organisms need organ systems to keep their cells alive.

Suggest what kind of tissue or organism a cell is part of, based on its features.

Explain how to use a microscope to identify and compare different types of cells.

Explain how uni-cellular organisms are adapted to carry out functions that in multi-cellular organisms are done by different types of cell.

AQA KS3 biology Extend

Make deductions about how medical treatments work based on cells, tissues, organs and systems.

Suggest how damage to, or failure of, an organ would affect other body systems.

Deduce general patterns about how the structure of different cells is related to their function.

Find out how recreational drugs might affect different body systems.

 

AQA KS3 biology 3.8.3 Breathing

AQA KS3 biology Investigate a claim linking height to lung volume

AQA KS3 biology Know

In gas exchange, oxygen and carbon dioxide move between alveoli and the blood.

Oxygen is transported to cells for aerobic respiration and carbon dioxide, a waste product of respiration, is removed from the body.

Breathing occurs through the action of muscles in the ribcage and diaphragm.

The amount of oxygen required by body cells determines the rate of breathing.

Keywords

Breathing: The movement of air in and out of the lungs.

Trachea (windpipe): Carries air from the mouth and nose to the lungs.

Bronchi: Two tubes which carry air to the lungs.

Bronchioles: Small tubes in the lung.

Alveoli: Small air sacs found at the end of each bronchiole.

Ribs: Bones which surround the lungs to form the ribcage.

Diaphragm: A sheet of muscle found underneath the lungs.

Lung volume: Measure of the amount of air breathed in or out.

AQA KS3 biology Apply

Explain how exercise, smoking and asthma affect the gas exchange system.

Explain how the parts of the gas exchange system are adapted to their function.

Explain observations about changes to breathing rate and volume.

Explain how changes in volume and pressure inside the chest move gases in and out of the lungs.

AQA KS3 biology Extend

Evaluate a possible treatment for a lung disease.

Predict how a change in the gas exchange system could affect other processes in the body.

Evaluate a model for showing the mechanism of breathing.
 

 

AQA KS3 biology 3.8.4 Digestion

Evaluate how well a model represents key features of the digestive system

AQA KS3 biology Know

The body needs a balanced diet with carbohydrates, lipids, proteins, vitamins, minerals, dietary fibre and water, for its cells’ energy, growth and maintenance.

Organs of the digestive system are adapted to break large food molecules into small ones which can travel in the blood to cells and are used for life processes.

Facts

Iron is a mineral important for red blood cells.

Calcium is a mineral needed for strong teeth and bones.

Vitamins and minerals are needed in small amounts to keep the body healthy.

Keywords

Enzymes: Substances that speed up the chemical reactions of digestion.

Dietary fibre: Parts of plants that cannot be digested, which helps the body eliminate waste.

Carbohydrates: The body’s main source of energy. There are two types: simple (sugars) and complex (starch).

Lipids (fats and oils): A source of energy. Found in butter, milk, eggs, nuts.

Protein: Nutrient your body uses to build new tissue for growth and repair. Sources are meat, fish, eggs, dairy products, beans, nuts and seeds.

Stomach: A sac where food is mixed with acidic juices to start the digestion of protein and kill microorganisms.

Small intestine: Upper part of the intestine where digestion is completed and nutrients are absorbed by the blood.

Large intestine: Lower part of the intestine from which water is absorbed and where faeces are formed.

Gut bacteria: Microorganisms that naturally live in the intestine and help food break down.

AQA KS3 biology Apply

Describe possible health effects of unbalanced diets from data provided.

Calculate food requirements for a healthy diet, using information provided.

Describe how organs and tissues involved in digestion are adapted for their role.

Describe the events that take place in order to turn a meal into simple food molecules inside a cell.

AQA KS3 biology Extend

Design a diet for a person with specific dietary needs.

Critique claims for a food product or diet by analysing nutritional information.

Make deductions from medical symptoms showing problems with the digestive system.
 

 

AQA KS3 biology 3.9 Ecosystems

AQA KS3 biology 3.9.1 Interdependence

Use a model to investigate the impact of changes in a population of one organism on others in the ecosystem

AQA KS3 biology Know

Organisms in a food web (decomposers, producers and consumers) depend on each other for nutrients.

So, a change in one population leads to changes in others.

The population of a species is affected by the number of its predators and prey, disease, pollution and competition between individuals for limited resources such as water and nutrients.

Fact Insects are needed to pollinate food crops.

Keywords

Food web: Shows how food chains in an ecosystem are linked.

Food chain: Part of a food web, starting with a producer, ending with a top predator.

Ecosystem: The living things in a given area and their non-living environment.

Environment: The surrounding air, water and soil where an organism lives.

Population: Group of the same species living in an area.

Producer: Green plant or algae that makes its own food using sunlight.

Consumer: Animal that eats other animals or plants.

Decomposer: Organism that breaks down dead plant and animal material so nutrients can be recycled back to the soil or water.

AQA KS3 biology Apply

Describe how a species’ population changes as its predator or prey population changes.

Explain effects of environmental changes and toxic materials on a species’ population.

Combine food chains to form a food web.

Explain issues with human food supplies in terms of insect pollinators.

AQA KS3 biology Extend

Suggest what might happen when an unfamiliar species is introduced into a food web.

Develop an argument about how toxic substances can accumulate in human food.

Make a deduction based on data about what caused a change in the population of a species.
 

 

AQA KS3 biology 3.9.2 Plant reproduction

Use models to evaluate the features of various types of seed dispersal

AQA KS3 biology Know

Plants have adaptations to disperse seeds using wind, water or animals.

Plants reproduce sexually to produce seeds, which are formed following fertilisation in the ovary.

Facts

Flowers contain the plant’s reproductive organs.

Pollen can be carried by the wind, pollinating insects or other animals.

Keywords

Pollen: Contains the plant male sex cells found on the stamens.

Ovules: Female sex cells in plants found in the ovary.

Pollination: Transfer of pollen from the male part of the flower to the female part of the flower on the same or another plant.

Fertilisation: Joining of a nucleus from a male and female sex cell.

Seed: Structure that contains the embryo of a new plant.

Fruit: Structure that the ovary becomes after fertilisation, which contains seeds.

Carpel: The female part of the flower, made up of the stigma where the pollen lands, style and ovary.

AQA KS3 biology Apply

Describe the main steps that take place when a plant reproduces successfully.

Identify parts of the flower and link their structure to their function.

Suggest how a plant carried out seed dispersal based on the features of its fruit or seed.

Explain why seed dispersal is important to survival of the parent plant and its offspring.

AQA KS3 biology Extend

Describe similarities and differences between the structures of wind pollinated and insect pollinated plants.

Suggest how plant breeders use knowledge of pollination to carry out selective breeding.

Develop an argument why a particular plant structure increases the likelihood of successful production of offspring.
 

 

AQA KS3 biology 3.9.3 Respiration

Use data from investigating fermentation with yeast to explore respiration

AQA KS3 biology Know

Respiration is a series of chemical reactions, in cells, that breaks down glucose to provide energy and form new molecules.

Most living things use aerobic respiration but switch to anaerobic respiration, which provides less energy, when oxygen is unavailable.

Fact Yeast fermentation is used in brewing and breadmaking.

Keywords

Aerobic respiration: Breaking down glucose with oxygen to release energy and producing carbon dioxide and water.

Anaerobic respiration (fermentation): Releasing energy from the breakdown of glucose without oxygen, producing lactic acid (in animals) and ethanol and carbon dioxide (in plants and microorganisms).

AQA KS3 biology Apply

Use word equations to describe aerobic and anaerobic respiration.

Explain how specific activities involve aerobic or anaerobic respiration.

AQA KS3 biology Extend

Suggest how organisms living in different conditions use respiration to get their energy.

Describe similarities and differences between aerobic and anaerobic respiration.
 

 

AQA KS3 biology 3.9.4 Photosynthesis

Use lab tests on variegated leaves to show that chlorophyll is essential for photosynthesis

AQA KS3 biology Know

Plants and algae do not eat, but use energy from light, together with carbon dioxide and water to make glucose (food) through photosynthesis.

They either use the glucose as an energy source, to build new tissue, or store it for later use.

Plants have specially-adapted organs that allow them to obtain resources needed for photosynthesis.

Fact Iodine is used to test for the presence of starch.

Keywords

Fertilisers: Chemicals containing minerals that plants need to build new tissues.

Photosynthesis: A process where plants and algae turn carbon dioxide and water into glucose and release oxygen.

Chlorophyll: Green pigment in plants and algae which absorbs light energy.

Stomata: Pores in the bottom of a leaf which open and close to let gases in and out.

AQA KS3 biology Apply

Describe ways in which plants obtain resources for photosynthesis.

Explain why other organisms are dependent on photosynthesis.

Sketch a line graph to show how the rate of photosynthesis is affected by changing conditions.

Use a word equation to describe photosynthesis in plants and algae.

AQA KS3 biology Extend

Suggest how particular conditions could affect plant growth.

Suggest reasons for particular adaptations of leaves, roots and stems.

Compare the movement of carbon dioxide and oxygen through stomata at different times of day.
 

 

AQA KS3 biology 3.10 Genes

AQA KS3 biology 3.10.1 Variation

Graph data relating to variation and explain how it may lead to the survival of a species

AQA KS3 biology Know

There is variation between individuals of the same species.

Some variation is inherited, some is caused by the environment and some is a combination.

Variation between individuals is important for the survival of a species, helping it to avoid extinction in an always changing environment.

Keywords

Species: A group of living things that have more in common with each other than with other groups.

Variation: The differences within and between species.

Continuous variation: Where differences between living things can have any numerical value.

Discontinuous variation: Where differences between living things can only be grouped into categories.

AQA KS3 biology Apply

Explain whether characteristics are inherited, environmental or both.

Plot bar charts or line graphs to show discontinuous or continuous variation data.

Explain how variation helps a particular species in a changing environment.

Explain how characteristics of a species are adapted to particular environmental conditions.

AQA KS3 biology Extend

Predict implications of a change in the environment on a population.

Use the ideas of variation to explain why one species may adapt better than another to environmental change.

Critique a claim that a particular characteristic is inherited or environmental.
 

AQA KS3 biology 3.10.2 Human reproduction

Relate advice to pregnant women to ideas about transfer of substances to the embryo

AQA KS3 biology Know

The menstrual cycle prepares the female for pregnancy and stops if the egg is fertilised by a sperm.

The developing foetus relies on the mother to provide it with oxygen and nutrients, to remove waste and protect it against harmful substances.

Facts

The menstrual cycle lasts approximately 28 days.

If an egg is fertilised it settles into the uterus lining.

Keywords

Gamete: The male gamete (sex cell) in animals is a sperm, the female an egg.

Fertilisation: Joining of a nucleus from a male and female sex cell.

Ovary: Organ which contains eggs.

Testicle: Organ where sperm are produced.

Oviduct, or fallopian tube: Carries an egg from the ovary to the uterus and is where fertilisation occurs.

Uterus, or womb: Where a baby develops in a pregnant woman.

Ovulation: Release of an egg cell during the menstrual cycle, which may be met by a sperm.

Menstruation: Loss of the lining of the uterus during the menstrual cycle.

Reproductive system: All the male and female organs involved in reproduction.

Penis: Organ which carries sperm out of the male’s body.

Vagina: Where the penis enters the female’s body and sperm is received.

Foetus: The developing baby during pregnancy.

Gestation: Process where the baby develops during pregnancy.

Placenta: Organ that provides the foetus with oxygen and nutrients and removes waste substances.

Amniotic fluid: Liquid that surrounds and protects the foetus.

Umbilical cord: Connects the foetus to the placenta.

AQA KS3 biology Apply

Explain whether substances are passed from the mother to the foetus or not.

Use a diagram to show stages in development of a foetus from the production of sex cells to birth.

Describe causes of low fertility in male and female reproductive systems.

Identify key events on a diagram of the menstrual cycle.

AQA KS3 biology Extend

Explain why pregnancy is more or less likely at certain stages of the menstrual cycle.

Make deductions about how contraception and fertility treatments work.

Predict the effect of cigarettes, alcohol or drugs on the developing foetus.
 

 

AQA KS3 biology 3.10.3 Evolution

Review the evidence for theories about how a particular species went extinct

AQA KS3 biology Know

Natural selection is a theory that explains how species evolve and why extinction occurs.

Biodiversity is vital to maintaining populations.

Within a species variation helps against environment changes, avoiding extinction.

Within an ecosystem, having many different species ensures resources are available for other populations, like humans.

Keywords

Population: Group of organisms of the same kind living in the same place.

Natural selection: Process by which species change over time in response to environmental changes and competition for resources.

Extinct: When no more individuals of a species remain.

Biodiversity: The variety of living things. It is measured as the differences between individuals of the same species, or the number of different species in an ecosystem.

Competition: When two or more living things struggle against each other to get the same resource.

Evolution: Theory that the animal and plant species living today descended from species that existed in the past.

AQA KS3 biology Apply

Use evidence to explain why a species has become extinct or adapted to changing conditions.

Evaluate whether evidence for a species changing over time supports natural selection.

Explain how a lack of biodiversity can affect an ecosystem.

Describe how preserving biodiversity can provide useful products and services for humans

AQA KS3 biology Extend

Predict and explain the changes in a population over time due to natural selection.

Suggest an explanation, based on data, for how a particular evolutionary change occurred.

Evaluate ways of preserving plant or animal material for future generations.
 

 

AQA KS3 biology 3.10.4 Inheritance

Model the inheritance of a specific trait and explore the variation in the offspring produced

AQA KS3 biology Know

Inherited characteristics are the result of genetic information, in the form of sections of DNA called genes, being transferred from parents to offspring during reproduction.

Chromosomes are long pieces of DNA which contain many genes.

Gametes, carrying half the total number of chromosomes of each parent, combine during fertilisation.

Facts

The DNA of every individual is different, except for identical twins.

There is more than one version of each gene eg different blood groups.

Keywords

Inherited characteristics: Features that are passed from parents to their offspring.

DNA: A molecule found in the nucleus of cells that contains genetic information.

Chromosomes: Thread-like structures containing tightly coiled DNA.

Gene: A section of DNA that determines an inherited characteristic.

AQA KS3 biology Apply

Use a diagram to show the relationship between DNA, chromosomes and genes.

Use a diagram to show how genes are inherited.

Explain how a change in the DNA (mutation) may affect an organism and its future offspring.

Explain why offspring from the same parents look similar but are not usually identical

AQA KS3 biology Extend

Suggest arguments for and against genetic modification.

Suggest benefits from scientists knowing all the genes in the human genome.

Determine how the number of chromosomes changes during cell division, production of sex cells and fertilisation.

Find out why scientists Watson, Crick and Franklin were so important.
 



OCR Twenty First Century Science knowledge and understanding expected before GCSE Biology

Chapter B1 You and your genes

From your Key Stages 1 to 3 science studies about genes and inheritance you should ...

know that living things produce offspring of the same kind, but normally offspring vary and are not identical to their parents

know that heredity is the process by which genetic information is transmitted from one generation to the next

know that genetic information is stored in the nucleus

understand a simple model of chromosomes, genes and DNA

know about the part played by Watson, Crick, Wilkins and Franklin in the development of the DNA model

know about sexual reproduction in animals, including the role of gametes and the process of fertilisation

know about sexual and asexual reproduction in plants, including flower structures and the processes of pollination and fertilisation

 

Chapter B2 Keeping healthy

From your Key Stages 1 to 3 science studies about on health and disease you should ..

appreciate that good hygiene helps humans keep healthy

be able to identify and name the main parts of the human circulatory system, and describe the functions of the heart, blood vessels and blood

appreciate the importance of bacteria in the human digestive system

know that animals, including humans, need the right types and amount of nutrition, and that a healthy human diet includes carbohydrates, lipids (fats and oils), proteins, vitamins, minerals, dietary fibre and water

recall some of the consequences of imbalances in the diet, including obesity, starvation and deficiency diseases

recognise the impact of diet, exercise, drugs and lifestyle on the way their bodies function

recall some of the effects of recreational drugs (including substance misuse) on behaviour, health and life processes.
 

Chapter B3 Living together – food and ecosystems

From your Key Stages 1 to 3 science studies about food and ecosystems you should ...

understand the similarities and differences between plant and animal cells

know that some organisms make their own food using photosynthesis

know that photosynthesis in plant cells occurs in the chloroplasts

know the reactants in, and products of, photosynthesis, and be able to write a word summary

know that photosynthesis requires light

be familiar with the adaptations of leaves for photosynthesis, and the role of stomata in gas exchange

know that water and minerals enter a plant through the roots

know that molecules of a solute move through solvent, and through cell membranes, by diffusion

know that animals obtain their food from plants (and other animals that ate plants)

understand the difference between carnivores, herbivores and omnivores, and between producers and consumers

know that individuals of the same type living in the same place make up a population, and that all the interacting populations in an ecosystem make up the community

understand the use of food chains and food webs as models of the feeding relationships within a community

appreciate the interdependence of organisms in a community, including food webs, the breakdown and cycling of materials, and animals as pollinators

know that changes in an ecosystem can affect the survival of individuals and populations.

 

Chapter B4 Using food and controlling growth

From your Key Stages 1 to 3 science studies about on cellular respiration and growth you should ...

be familiar with the processes of aerobic and anaerobic respiration in living organisms, and fermentation in microorganisms, including word summaries of the reactions

be able to recall the differences between aerobic and anaerobic respiration in terms of the reactants, products and implications for the organism

be familiar with the tissues and organs of the human digestive system, including adaptations to function

understand in simple terms that the human digestive system uses chemicals (including enzymes) to digest food

appreciate the importance of bacteria in the human digestive system

know how nutrients and water are transported within animals, including humans.

 

Chapter B5 The human body – staying alive

From your Key Stages 1 to 3 science studies about on the human body you should ...

appreciate the hierarchical organisation of multicellular organisms: from cells to tissues to organs to systems to organisms

be able to identify, name, draw and label the basic parts of the human body

have a basic understanding of the function of muscles

be familiar with the tissues and organs of the human digestive system, including adaptations to function

understand the basic structures and functions of the gas exchange system in humans, including adaptations to function

understand the mechanism of breathing to move air in and out of the lungs, and be able to use a pressure model to explain the movement of gases

understand, in outline, how nutrients and water are transported within animals, including humans

be able to identify and name the main parts of the human circulatory system

be familiar with the functions of the heart, blood vessels and blood

know which part of the body is associated with each sense.

 

Chapter B6 Life on Earth – past, present and future

From your Key Stages 1 to 3 science studies about evolution and biodiversity you should ...

know that there are many different types of organisms living in many different environments, and that there are similarities and differences between all organisms

recognise that living organisms can be grouped and classified in a variety of ways based on commonalities and differences

be able to use classification keys

recognise that living organisms have changed over time and that fossils provide information about organisms that lived millions of years ago

appreciate that organisms live in habitats to which they are adapted

recognise that organisms produce offspring of the same kind, but normally offspring vary and are not identical to their parents

know that there is variation between individuals within a species, and that variation can be described as continuous or discontinuous

understand that the variation means some organisms compete more successfully, resulting in natural selection

appreciate that variation, adaptation, competition and natural selection result in the evolution of species

understand that changes in the environment may leave organisms less well adapted to compete successfully and reproduce, which can lead to extinction

be familiar with some of the reasons why it’s important to protect and conserve biodiversity, and some ways of doing so.

 



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 Doc Brown's Revision  KS3 Science - KS3 BIOLOGY Unit 7A Cells

KS3 Biology About the unit

In this unit pupils:

  learn that cells are the basic units of life and are organised into tissues from which organs are made

  explore cell structure and differences between plant and animal cells

  learn about some functions of cells

In scientific enquiry pupils:

  learn how observations made with a microscope helped ideas about the structure of living things to develop

  learn to use a microscope safely and effectively

  make observations using a microscope and record these in drawings

  compare and interpret information from microscopic observation

  draw conclusions from observations and explain these using scientific knowledge

  are introduced to the importance of sampling in biological investigations

  carry out an investigation into the growth of pollen tubes, controlling relevant variables and taking account of those which cannot be controlled

Much of this work involves the interpretation and analysis of visual information gathered from a variety of sources. The use of enlarged images and microprojection apparatus may support learning for pupils with visual impairment. Extra support may be required by pupils with poor manipulative skills, in preparing materials for microscopic examination, in the effective use of a microscope and when using a computer or other drawing aid to record their observations.

KS3 Biology Where the unit fits in

This unit draws on ideas developed in the key stage 2 programme of study. It relates to unit 5A ‘Keeping healthy’ and unit 6B ‘Micro-organisms’ in the key stage 2 scheme of work.

The unit relates closely to unit 7B ‘Reproduction’ and unit 7D ‘Variation and classification’. It provides an introduction to ideas and experimental techniques which pupils may not have encountered in the key stage 2 scheme of work.

It provides the foundation for work on cells in all year 8 and year 9 units.

 

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: describe some earlier ideas about the structure of living things and relate these to evidence from microscope observations; make observations using a microscope and record them in simple drawings; suggest a question about pollen tubes that can be investigated and use an appropriate sample; present results in an appropriate graph, explaining what these show

some pupils will not have made so much progress and will: relate drawings to observations made using a microscope and describe what they found out from their investigation

some pupils will have progressed further and will: explain how evidence from microscope observations changed ideas about the structure of living things; estimate sizes of specimens viewed under the microscope and justify the sample chosen in an investigation of pollen tubes

in terms of life processes and living things

most pupils will: identify and name features of cells and describe some differences between plant and animal cells; explain that growth occurs when cells divide and increase in size; describe how cells are grouped to form tissues

some pupils will not have made so much progress and will: recognise that all organisms are made from cells and name some parts of a cell

some pupils will have progressed further and will: recognise that viruses are not cells and describe how some cells in an organism are specialised to carry out particular functions

KS3 Biology Prior learning

It is helpful if pupils know:

  the names and functions of some major organs in plants and animals

  about some of the life processes common to living things, eg movement, growth, reproduction, nutrition

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity. In this unit pupils:

  use a variety of stains for cells

  work with animal materials

  plan and carry out their own investigation

Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  words relating to the structure of organisms, eg organ, tissue, cell

  more specialised words relating to cells, eg membrane, cytoplasm, nucleus, chloroplast, vacuole

  words with similar but distinct meanings, eg membrane and skin, or terms that they regularly interchange, eg cell wall and membrane

  words with different meanings in scientific and everyday contexts, eg cell, wall, tissue

  words and phrases relating to scientific enquiry, eg variable, sample size, evaluate, magnification

Through the activities pupils could:

  use skimming, scanning, highlighting and note taking as appropriate to different texts

KS3 Biology Resources

Resources include:

  secondary sources to explore cell structure and the variety of cell types in animals and plants, eg CD-ROMs, internet, photographs at high magnification (which may be copied onto overhead transparencies (OHTs)), video clips, other literature

  literature relating to Hooke’s work on cells

  microscopes and/or bioviewers

  eyepiece graticules or strips of graticule photographs

  prepared slides showing human cheek cells and a range of human and plant cells, some of which illustrate cell specialisation

  materials for making model cells

  suitable plant material for microscope observation, eg onion, tomato, potato, moss, filamentous green algae, fresh garlic roots, large flowers ripe with pollen and ovules

  photographs or video clips of dividing cells and developing human embryos

  slides of pollen grains to illustrate developing pollen tubes

KS3 Biology Out-of-school learning

Pupils could:

  visit libraries or museums to find out more about the importance of cells to our lives, eg cancer as a disease resulting from cell malfunction, tissue grafting to repair burns

  use the internet to examine images of cells, eg www.cellsalive.com

  read newspaper articles and watch television programmes relating to the topic

  find out about the history of the microscope, including the light microscope and electron microscope and their use in developing our understanding of the organisation of living things

   KS3 Biology  What are living organisms made from?

   that plants and animals contain organs

   that tissues make up organs

   to draw inferences from data

   Review pupils’ knowledge of the organs of plants and humans, asking them to name, identify and show where these organs are found by using models and/or by labelling diagrams. Ask questions about the roles these organs play in the life of the organism, and the nature of important life processes.

   Challenge pupils to consider what the organs of the body are made of, and introduce the idea of tissues. Show images of a range of organic structures, eg on video, CD-ROM, OHT slides. Ask pupils to make inferences about the structure of living things from this evidence.

  identify, locate and describe the functions of a range of plant and human organs

  make suggestions about the structure of living things from microscope evidence

  state that living things are made up of different types of tissue, which is made up from very small units

   This activity is intended to help teachers find out what pupils know and understand about the organisation of organs in plants and humans and about life processes. Teachers will need to bear this in mind when planning later activities.

   KS3 Biology How can using a microscope give us information about structure?

   to use a microscope safely and effectively

   to prepare simple specimens on a slide for observation using a microscope

   to make observations using a microscope and to record these as drawings

   Ask pupils about using magnifying glasses and microscopes to make detailed observations, and find out what they understand about magnification.

   Demonstrate the correct use of the microscope to make observations under low magnification. Help pupils to use a prepared slide of newsprint, eg the letter ‘e’, to practise placing and focusing slides.

   Help pupils make slides of common objects, eg sand, newsprint, tissue paper, hair. Encourage them to record observations in clear drawings, eg by showing them prepared drawings and asking them to identify what is clear and unclear in them. Establish through questioning why it is important to include the level of magnification.

  prepare a specimen for microscopic observation, and correctly focus the microscope to view it

  describe how the objects appear under low magnification

  make careful drawings of the objects viewed

   Some pupils find it difficult to focus microscopes. It may be helpful to set up microscopes already focused on specimens or use bioviewers alongside microscopes.

   Pupils with physical disability could be offered the opportunity to provide instructions to another pupil to demonstrate their knowledge and understanding about preparing specimens for microscopic observation.

   Making measurements of cells can help pupils to develop an understanding of very small numbers. Eyepiece graticules, or strips of graticule photographs as cheaper alternatives, can be useful resources when making measurements.

   Extension: some pupils may be ready to explore ways of measuring the size of objects observed, by measuring the diameter of the field of view and estimating size against this measure, or by devising their own method.

Safety

– there is a risk from reflected sunlight when using daylight for mirror illumination with microscopes

    KS3 Biology How can using a microscope give us information about structure? (Cont.)

   to use skimming, scanning, highlighting and note taking as appropriate to different texts

   how ideas about the structure of living things have changed

   that plants and animals are made up of cells

   that plant and animal cells are similar in a number of respects, but have significant differences

   to make observations using a microscope

   Show pupils evidence of the early observations made by Robert Hooke and others to illustrate how the development of the microscope changed the way in which scientists viewed the structure of living things. Ask pupils to find out how ideas developed. Provide opportunities for pupils to read different types of text, reminding them of ways of identifying key points, and to discuss findings in groups before reporting back to the whole class, eg using flow charts or a series of annotated diagrams.

   Introduce the term ‘cell’ and show pictures and/or three-dimensional models of a range of cell types from animals and plants. Help pupils to prepare slides of pieces of plant material, eg leaf surface, petals, root, squash, potato and tomato scrapings, onion epidermis. Establish that plant material is made of cells. Ask pupils to describe these cells.

   Provide opportunities for pupils to make their own slides of cheek cells as well as to observe prepared slides of human cells. Ask pupils to suggest ways in which these cells are similar to and different from plant cells. Demonstrate by drawing around a single cell in the photograph, or by drawing a cell which you can see and then showing this particular cell to a pupil, to help to focus their perception and observations.

  describe some earlier ideas about the structure of living things

  identify key points using an appropriate technique

  explain how evidence from microscope observations led to new ideas

  state that living things are made of microscopic units called cells

  draw the cells observed

  identify observable similarities and differences between cells

  make a generalisation about the differences, eg in size, presence of thick outer wall, between plant and animal cells

   Much material relating to the development of our understanding of cells and the contributions made by the microscope is available on the internet. A search beginning with ‘Robert+Hooke’ may provide useful resources.

   Details of cell structure visible at higher magnification are not required, eg mitochondria.

   Pupils often have difficulty in recognising individual cells. Careful demonstration with the whole class, using a microprojector or an OHT of cell photographs, can help overcome this problem.

   Extension: some pupils could use moss to observe chloroplasts.

Safety

– a risk assessment may be required in relation to the types of stain that might be used

– allow pupils to use a cotton bud to take their own samples and dispose of the cotton bud safely. Check school/LEA risk assessments for cheek-cell sampling

    KS3 Biology What are cells like?

   that plant and animal cells are similar in a number of respects

   that plant and animal cells have a cell surface membrane which keeps the cell together and controls what enters and leaves

   that cells have cytoplasm which occupies most of the cell

   that cells have nuclei which control activities of the cell

   that there are significant differences between plant and animal cells

   Show, and help pupils to make, three-dimensional models of plant and animal cells, eg using small plastic bags filled with cellulose paste to represent cytoplasm, with suitable objects to represent the nucleus (plant cells can also be made if the bags are squeezed into boxes).

   Ask pupils to identify what plant and animal cells have in common and how they are different, and help them relate the models to cells they have observed, and to drawings, diagrams, and photographs of cells. Establish that the diagrams represent a ‘view’ of the cell from one aspect.

   Provide pupils with secondary sources of information about cells, eg CD-ROMs which allow virtual reality cell exploration, such as a voyage through a cell. Ask them to produce an account, eg ‘My journey through a cell’. Compare accounts of plant and animal cells to begin to identify differences between them.

   Review the parts of the cells, with pupils identifying that plant and animal cells contain cytoplasm, cell membrane and nucleus, and that plant cells also have a cell wall, almost always a vacuole and often chloroplasts.

  relate the parts of model cells to diagrams and pictures of plant and animal cells

  describe what plant and animal cells have in common

  identify that plant cells have a cell wall and vacuole and may have chloroplasts, but that animal cells do not

   Making cell models is useful because it enables pupils to appreciate the 3-D structure of cells. However, models have limitations, eg presenting a static rather than a dynamic model of the cell. Pupils could discuss these.

   Models of cells could also be prepared from different colours of modelling clay, with a central nucleus. These can be cut into sections to demonstrate different views.

Safety

 it is best to use cellulose paste because wallpaper paste contains fungicide

    Checking progress

   to relate ideas about cells and cell structure

   Present pupils with a collection of pictures, models, CD-ROMs of specialised cells, eg epithelial cell, root hair, pollen, palisade cell, neurone, sperm, egg, red blood cell. Ask them to classify each cell as plant or animal in origin, giving reasons, and to label the parts of the cells which they can identify.

  classify cells as plant or animal in origin, giving reasons, and label parts of cells 

 

    KS3 Biology What do cells do?

   that there are different types of cell, adapted for different functions

   to use secondary sources of information

   Review with pupils pictures, models or CD-ROMs of some specialised cells, eg epithelial cell, root hair, pollen, neurone, sperm, egg, red blood cell. Provide information about the role of each type of cell and ask pupils to match these to each cell.

   Show pupils how to use secondary sources to find out more about specialised cells in plants and animals, and how to present this information as a report on a cell type. Use this activity as an opportunity to emphasise that cells are dynamic systems rather than static structures.

  explain that different types of cell can be found in plants and animals, and that these cells carry out specialised functions

  identify specialised features in different types of cell, and relate these to the function of a cell

  find and present relevant information on a particular
cell type

   Consideration of different types of cell in plants and animals is used to reinforce work on parts of cells, and on similarities and differences between cells in plants and animals.

   At this stage pupils do not need to know about the structure of viruses. However, some pupils will find from secondary sources that they are not cells.

   Pupils will have opportunities to relate cell adaptations to life processes in unit 7B ‘Reproduction’ and unit 9C ‘Plants and photosynthesis’.

   that cells form tissues, and tissues form organs

   to name some important tissues in plants and humans

   to explain the organisation of tissues, using a model

   Introduce the concept of a tissue, naming examples relating to specialised cells previously observed. Use the analogy of a house to explain the organisation of tissues, showing that different materials are used to make different parts, and that these parts make the whole. Help pupils to model this, using building sets to make the equivalent of tissues, and using these to build a house or an organ of their choice.

   Show pupils a dissection, eg of a hen’s leg, to illustrate the different types of tissue in a complex structure.

   Show pupils a privet leaf as an example of a plant organ, explaining that it is made from different types of cell organised into tissues.

   As an alternative some pupils could provide cartoons or drawings to show and explain how various tissues make up an organ.

  name some examples of tissues from plants and humans

  relate the different parts of a model to the cells and tissues making up an organ in a living organism

   At this stage, pupils are introduced to the idea of hierarchical organisation of cells into tissues and organs. They do not need to know details of structure and function of tissues.

   Extension: pupils may be familiar with the idea of tissue grafting, or bone marrow transplants. They could be asked to find out more about these.

   Extension: pupils could observe prepared slides, eg of a transverse section of a privet leaf, identifying the occurrence and distribution of different cell types and tissues, and relating this to the structure of the leaf as an organ.

Safety  

– disinfect the bench after the dissection

    KS3 Biology How are new cells made?

   that cells can make new cells
by dividing

   that growth occurs when new cells are made and increase
in size

   that cell division begins with division of the nucleus

   Ask pupils how they think new cells are made, and discuss different ideas that may arise.

   Provide plant material to illustrate active cell division, eg filamentous green algae, budding yeast, broad bean roots, for microscope examination under low magnification. Ask pupils to suggest how they might identify cells that are making new cells, and to locate and identify cells that may have recently divided, giving reasons.

   Using these observations and secondary sources of evidence, eg photographs or video images of dividing cells, help pupils to sequence photographs of cell division. Prompt them with questions, eg Why does the nucleus divide first? Consolidate by providing pupils with diagrams of the same process to sequence and annotate.

  explain that growth of living things occurs by cells dividing to make new cells, and these cells increasing in size

  represent the process of cell division as a sequence that begins with division of the nucleus

   Check plant material before the lesson to ensure examples of dividing cells can be observed. Filamentous green algae collected from a pond provide evidence of recently divided cells, about half the size of the typical cell in the filament.

   As an alternative, use prepared slides which show dividing cells.

   Details of cell division are not required. Mitosis forms part of the key stage 4 programme of study.

   that cells have nuclei containing the information that is transferred from one generation to the next

   that in plants, pollen and ovule are specialised cells which enable information to be transferred from one generation to the next

   that at fertilisation, nuclei from pollen and ovule fuse to make a new and unique individual

   Ask pupils what they remember about pollination and sexual reproduction in plants. Extend their ideas about pollen and ovule by establishing that these are the male and female reproductive cells of plants, and help them to observe pollen and ovules under the microscope at low magnification. Describe the process of fertilisation in plants as the transmission of information within a nucleus of the pollen grain to the ovule, and the combination of the nuclei of ovule and pollen grain to form a new cell. Prepare slides of pollen grains, eg from lilies, in 10% sugar solution and help pupils to observe the growth of pollen tubes. Establish that the new cell grows to form a seed, making new cells by division.

  explain the process of fertilisation in flowering plants as the transfer of information within nuclei from parents to offspring

  distinguish between the processes of pollination and fertilisation in flowering plants

  make drawings to illustrate the sequence of events during fertilisation in plants

   Pupils should be familiar with sexual reproduction in plants and with flower structure from work at key stage 2.

   Details of fertilisation in flowering plants are not required at this stage. Fertilisation in plants and animals will be revisited in unit 9A ‘Inheritance and selection’ and fertilisation in humans is described in unit 7B ‘Reproduction’.

   Pollen and ovules are easily observed in any simple flower with large stamens and ovaries, eg wallflower, daffodil, godetia, nasturtium, tulip. A range of flowers from the same species will provide pollen at different stages of maturity.

    KS3 Biology What causes pollen tubes to grow?

   how to frame a question that can be investigated

   about the importance of sample size and the number of observations in biological investigations

   to identify trends shown
in graphs

   to evaluate the strength of the evidence

   Remind pupils of their observations of pollen tubes and explain that they are going to find the sugar concentration that is best for pollen tube growth. Help them to frame a question for investigation. Suggest an appropriate range of sugar concentrations and discuss with pupils the control of variables and the sort of observations which would provide the information needed to answer the question.

   Explain issues relating to sampling in biological investigations, eg sufficient sample size to account for variables that cannot be controlled or to provide reliable data.

   Help pupils to collect and present data relating to the number of germinated grains, in a sample of approximately 20, from each sugar concentration.

   Ask pupils to produce an account of their investigation in which the importance of sampling is clearly explained.

  identify a suitable question

  explain why they needed to use a particular number of pollen grains, eg 20 grains at each concentration

  make accurate observations and record these appropriately

  draw an appropriate graph of data collected

  use the graph to identify trends and make generalisations

  compare graphs produced by different groups, and use these to evaluate the strength of evidence

   This investigation provides an opportunity to help pupils understand the importance of sampling in biological investigations. A suitable approach involves preparing slides of pollen in a range of sugar concentrations, observing, eg 20 pollen grains from each slide, and counting how many of these have germinated. The use of 20 pollen grains should enable a conclusion to be drawn about the optimum concentration for the process. However, within each 20 grains there will be differences arising from variables that cannot be controlled,
eg the genetic make-up of the grain. In smaller samples these differences may mask the effect of the different concentrations of sugar.

Safety

pupils’ plans must be checked for health and safety, before practical work begins

    KS3 Biology Reviewing work

   about types of cells, their functions and organisation into tissues and organs

   to relate ideas about cell division to growth

   Provide images or video sequences of different specialised cells and of division and growth, eg early stages of a human embryo, together with short descriptions, and ask pupils, in groups, to match image and description. Discuss with them the examples that they have difficulty agreeing on. Ask them to use their work to help them make a summary sheet about the unit.

  identify different types of cell and describe their roles

  explain that growth occurs as a result of cell division and increase in size

 

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 Doc Brown's Revision  KS3 Science - KS3 Biology Unit 7B Reproduction

KS3 Biology About the unit

In this unit pupils:

  extend their earlier ideas about human reproduction and consider how offspring are protected and nurtured

  consider and compare reproductive patterns in other animals with those in humans

  relate what they know of the way their bodies change during adolescence to knowledge about human reproduction, growth and the menstrual cycle

In scientific enquiry pupils:

  consider sample size in biological investigations

  present data in bar charts and graphs

  interpret data they have collected and data from secondary sources

Teachers should make reference to their school’s sex-education policy and personal, social and health education (PSHE) programme. They will also be aware of the need for sensitivity to the personal circumstances of pupils and their families.

KS3 Biology Where the unit fits in

This unit draws on ideas developed in the key stage 2 programme of study. It builds on unit 5B ‘Life cycles’ in the key stage 2 scheme of work and on unit 7A ‘Cells’.

This unit relates to:

  PSHE

  drugs education

  sex education

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: select information about reproduction from secondary sources; present and interpret data about growth in bar charts and graphs, indicating whether increasing the sample they used would have improved the work

some pupils will not have made so much progress and will: with help, find information from selected secondary sources and present data in tables and bar charts

some pupils will have progressed further and will: explain whether the sample size in their investigation of growth was sufficient for comparisons to be made with national data and describe how reproduction was explained before the role of cells was understood

in terms of life processes and living things

most pupils will: identify and name the main reproductive organs and describe their functions; describe fertilisation as the fusion of two cell nuclei; describe egg and sperm cells; explain how the foetus obtains the materials it needs for growth; describe differences between the gestation periods and the independence of the young of humans and other mammals and describe the menstrual cycle

some pupils will not have made so much progress and will: identify and name the main reproductive organs; describe fertilisation as the fusion of egg and sperm and identify the importance of the placenta in supplying food for a developing foetus

some pupils will have progressed further and will: explain how egg and sperm cells are specialised, and describe how they carry the information for development of a new life

KS3 Biology Prior learning

It is helpful if pupils:

  can describe the human life cycle in terms of infancy, childhood, adolescence, maturity and ageing

  know that organisms are made of cells which have a nucleus and that cells are adapted for their functions

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity. Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  names of reproductive organs, eg ovary, testis, oviduct, uterus

  specialised terms, eg menstruation, ovulation, fertilisation, placenta, mammary glands, sperm, gestation

  words with similar but distinct meanings, eg hereditary and inherited, baby and foetus, puberty and adolescence

  words with different meanings in scientific and everyday contexts, eg cell, fuse

  words relating to scientific enquiry, eg reliability, sample size, national data

Through the activities pupils could:

  make notes, summaries, etc to clarify ideas and thinking which can be used later

  plan and develop ideas and lines of thinking into continuous text

  join ideas within sentences including using links of time (then, later, meanwhile) and cause (so, because, since)

  collaborate with others to share information and ideas, and solve problems

  answer questions using relevant evidence or reasons

KS3 Biology Resources

Resources include:

  secondary sources: video clips, photographs about reproduction in animals, eg fish, frogs, where fertilisation is external

  video clips, models, photographs, software simulations and ultrasound scans illustrating the human reproductive organs, fertilisation, gestation, birth, menstruation and the menstrual cycle

  secondary sources providing information about the effects of alcohol, tobacco and other drugs, and rubella on the developing foetus

  video clips showing responses of a newborn baby and other animals, eg deer, birds, kittens, immediately after birth/hatching

  data about egg production, gestation time, time to maturity, survival rates of humans and other species

  data, eg height/weight charts, showing expected ranges

  secondary sources providing information about height/weight/growth of human offspring in the past

  access to ICT data-handling package

KS3 Biology Out-of-school learning

Pupils could:

  find out about reproduction of, and breeding in, domestic pets

  read newspaper and magazine articles about cloning

  find out about life-support systems for premature babies and children with prenatal developmental problems

  find out about social, ethical and technological issues when offspring are born as the result of assisted conception, such as ‘test-tube’ babies and fertility drugs

  find out whether height and weight charts from doctors and slimming organisations are the same or different

    KS3 Biology How does a new life start?

   that animals have different patterns of reproduction and development

   to make notes, summaries, etc to clarify ideas and thinking which can be used later

   Provide pupils with stimulus material, eg pictures, video clips, to review their knowledge of reproduction in animals. Ask pupils to find out about the reproduction and development of certain animals, eg fish, frogs, including information on fertilisation using texts, CD-ROMs and to make notes or summaries of their ideas.

   Discuss how eggs are fertilised externally in some animals, eg fish, frogs, using video clips as illustrations and pointing out the numbers of eggs fertilised at one time. Ask pupils to suggest why this is.

  state that a new life starts when a sperm fertilises an egg

  suggest reasons why large numbers of eggs, eg of fish and frogs, are fertilised at one time

  note key points about the reproduction of a particular animal

   Extension: pupils could be asked to find out about theories of reproduction, eg the homunculus theory, held before cells were discovered.

   that animals have different patterns of reproduction and development

   to draw conclusions from patterns in data

   that newborn human babies are more dependent than offspring of some other species

   Remind pupils of the differences in the number of eggs produced by animals where fertilisation is external and those where it is internal. Provide pupils with stimulus material and secondary sources and ask them to identify patterns in the number of eggs, internal and external fertilisation or development, aftercare, growth pattern and chance of offspring surviving to maturity in the species used.

   Discuss the advantages of retaining the young in the body and feeding the young on milk after birth, eg continuous access to nutrients, protection from predators. Show pupils video clips of other mammals’ offspring immediately after birth and ask them about their experience of newly born pets. Establish that newborn humans are more dependent than some other species. Help pupils to agree some broad generalisations from the data considered.

  state that mammalian young are fertilised internally and develop in the uterus

  explain that an advantage of internal development over external is that there is a greater chance of developing eggs surviving to become independent young

  draw conclusions about mammalian reproduction, eg some mammals have large numbers of offspring with a relatively small investment in aftercare, others have fewer offspring with a high degree of aftercare

   Extension: pupils could be encouraged to comment on advertising campaigns aimed at getting parents to talk to their children, then to think about how parents provide for children’s emotional as well as physical needs.

   As an alternative, pupils could compare the advantages and disadvantages of internal versus external fertilisation. Pupils could follow this up with group discussion, before summarising their own viewpoints in writing.

    KS3 Biology How does a new life start? (Cont.)

   the structure and function of the human male and female reproductive organs

   that fertilisation involves the fusion of the nuclei of sperm and egg

   that the fertilised egg divides into 2, 4, 8, etc cells as it passes down the oviduct

   Using models, video clips or other illustrations, help pupils to identify, name and describe the functions of the mature human reproductive organs. Ask pupils to annotate diagrams of male and female reproductive organs.

   Remind pupils of work on cells and establish that for fertilisation to occur, a male cell (sperm) fuses with a female cell (egg). Establish that sperm are produced in testes and eggs in ovaries. Talk with pupils about sperm being deposited in the vagina and having to move to where the eggs are and eggs being moved down the oviduct, illustrating, eg with video and software simulations. Explain fertilisation in terms of the fusion of nuclei of sperm and egg.

   Discuss with pupils, illustrating with, eg video clips, photographs, software simulations, how the cells divide and increase in number. Ask pupils to draw, or label, and sequence pictures or diagrams illustrating ovulation, fertilisation, cell division and implantation.

  name, locate and describe the functions of the reproductive structures, eg ovary, oviduct, uterus, vagina, penis, testis, sperm duct

  describe fertilisation in terms of the fusion of cells

  sequence changes in sperm and eggs during and after ovulation

   This provides an opportunity to discuss how infertility may arise, eg from low sperm counts, blocked oviducts or infrequent ovulation, the technological solutions available and some ethical and social issues that may arise.

   Teachers may wish to point out that an unfertilised egg will not survive more than three days, although sperm may remain alive for longer.

   that sperm and egg cells are specially adapted for their functions

   Show photographs or video clips of sperm and egg cells. Ask pupils to compare them and suggest how they are specially adapted for their functions. Ask pupils to draw and describe or annotate drawings of egg and sperm cells, identifying their main features.

  identify and describe how sperm cells are adapted to their functions, eg a tail that pushes it along; streamlining, by reduction in size through having less cytoplasm; a specially strengthened head that contains chemicals to penetrate and break down the outer layers of the egg

  identify and describe how egg cells are adapted to their functions, eg an enlarged cell with food reserves

   This work draws on unit 7A ‘Cells’.

   Extension: discussion of the adaptations of cells could be extended to the ciliated cells in the oviduct.

    KS3 Biology How does a new life start? (Cont.)

   that male and female nuclei contain the characteristics of male and female parents respectively

   Use quick questions to check pupils’ recall of cell structure and making new cells. Review fertilisation in terms of the fusion of nuclei and discuss how this results in characteristics being passed from parents to offspring.

   Ask the pupils to speculate on how identical and non-identical twins occur, eg by providing them with statements containing correct and incorrect explanations from which to select.

   Establish with pupils that, whether fertilisation is internal or external, it involves the fusing of male and female nuclei and involves the combination of characteristics of both parents.

  explain that sperm and egg each contain half the inherited information needed and relate this to the concept of identical and non-identical twins

   This work provides opportunities for pupils to relate ideas about inheritance to themselves. Teachers will be aware of the need to be sensitive to the circumstances of individuals and of their families.

   Detail about mitosis is not required at key stage 3.

    KS3 Biology When can human fertilisation take place?

   that egg cells are released from the ovaries at regular (approximately monthly) intervals

   that menstruation is a monthly cycle which stops during pregnancy

   that the stages in the menstrual cycle are controlled by hormones

   Remind pupils of the differences between external and internal fertilisation. Ask them about the numbers of eggs and sperm in each case and to suggest reasons for any differences. Find out what pupils know about human egg cells, eg where they are produced, how often they are produced, and how a woman might know if she is pregnant or not. Using pupils’ suggestions and video or CD-ROM simulation introduce the stages of the monthly cycle.

   Help the pupils to construct a diagram of the days in the cycle, marking when menstruation and ovulation might occur and when the uterus lining is thickening. Discuss with pupils the variation in cycle length and practise calculating when a woman might ovulate and when her period is due. Explain that the menstrual cycle also prepares the uterus for a fertilised egg and identify the time in the cycle when fertilisation is most likely.

   Establish that, on the whole, humans have one offspring at a time and that the human reproductive system is designed to try to make sure that the one offspring survives.

  describe the changes of the menstrual cycle, eg egg maturation, ovulation, menstruation

  recognise egg production as a cyclic activity

  make calculations, eg ovulation date and menstruation date, for a regular cycle

   This work provides an opportunity to discuss other changes related to menstruation and to answer questions raised by both boys and girls.

   At this stage pupils do not need to know about oestrogen or progesterone changes, or that egg development is stimulated by a hormone produced by the brain and changes in the uterus are controlled by hormones produced by the ovaries.

   Personal-hygiene companies offer visits by health professionals to support girls in the early years of puberty. They can also provide support for boys and mixed groups.

   These activities provide an opportunity to discuss with pupils the reasons for, and some outcomes of, multiple births.

    KS3 Biology How is the human foetus supported as it develops?

   that the foetus develops within a membranous bag and is supported and cushioned by amniotic fluid

   that the placenta supplies nutrients and oxygen to the foetus via the umbilical cord, and removes carbon dioxide and other waste products

   Use quick questions to establish pupils’ knowledge of pregnancy. Use photographs, models, diagrams, video clips, CD-ROMs or ultrasound scans to look at the changes in a developing foetus from implantation to birth and discuss the sequence with pupils.

   Identify the structures within the pregnant uterus and explain the functions of the amnion and amniotic fluid. Discuss with pupils the foetus’ need for nutrients and explain the role of the placenta in materials exchange. Ask pupils to label a diagram and use arrows to show movement of oxygen and nutrients from the mother to the foetus and the movement of carbon dioxide and other waste products from the foetus to the mother.

  identify the structures in a pregnant uterus and explain the function of amniotic fluid, eg supporting the foetus, cushioning against shocks

  describe the general route
taken by nutrients from the mother’s digestive system to
the foetus’ brain

  state that oxygen, water and digested food pass from the mother’s blood to the foetus’ blood and that carbon dioxide and other waste products pass in the opposite direction

   Several teaching schemes include photocopiable templates for making models of the foetus in the uterus.

   that harmful substances and viruses can cross the placenta into the foetus and affect development

   Challenge pupils to explain why, at one time, teenage girls were offered the rubella vaccine, but boys were not. Using secondary sources, discuss with pupils the passage of alcohol, substances from cigarette smoke and drugs across the placenta. Ask pupils to make a poster or leaflet to explain, eg why vaccination against rubella is important, how smoking can affect a developing foetus.

  include in their poster or leaflet appropriate information about the effects of alcohol, smoking or drugs on a developing baby’s growth

  recognise that pregnant women should avoid rubella

   This work provides an opportunity to undertake a risk assessment on the effects of smoking on the unborn child.

   Other effects of harmful substances are covered in unit 9B ‘Fit and healthy’.

    KS3 Biology What do newborn babies need?

   that uterine muscle contracts during birth, expelling the foetus and placenta through the vagina

   that the baby is nourished by milk from mammary glands, which provides nutrients and protects from infection

   Discuss with pupils the processes of birth, using video, photographs and diagrams as illustrations.

   Ask pupils how newborn babies obtain the nourishment they need. Describe the composition of breast milk. Review with pupils their knowledge of the care needed by babies.

   Use video clips to show that a baby is responsive to its world, eg has reflex actions when born, such as head turning when its cheek is touched.

  explain the process of birth as cervix muscles relaxing, uterus muscles contracting, and the foetus being pushed out, usually head first, with the placenta expelled afterwards

  describe how a newborn baby obtains the nutrients it needs for growth

  recognise that breast milk contains antibodies that
protect against common
micro-organisms 

   Extension: premature babies receive technological support in countries where such facilities are available, eg use of incubators and light treatment for jaundice, and pupils could investigate what life-support systems are needed.

   Extension: pupils could examine data on the slight reduction in survival rate of both very small and very large babies and speculate on the factors that can lead to these conditions, eg smoking linked with low birth weight.

    KS3 Biology Checking progress

   to summarise and make connections between key ideas in the unit

   to plan and develop ideas and lines of thinking into continuous text

   Ask pupils to produce a short illustrated account of the growth of a foetus and birth, which could be used with a younger sibling when a new baby is about to arrive in the family. Ask them for their ideas of the main points to include and how to organise the material.

  produce an account identifying key points and linking them in an appropriate sequence, using links of time and cause

   A writing frame could profitably be used to give structure to this activity.

    KS3 Biology How do humans change as they grow?

   that periods of rapid growth occur during the human life cycle

   to decide what sort of graph is appropriate

   Use quick oral questions to elicit pupils’ knowledge of the human life cycle, eg babyhood, childhood, adolescence, puberty and adulthood.

   Ask pupils to recall times when they grew rapidly in primary school and identify the main ways in which they changed. Use secondary data of height at different ages to plot growth charts and identify the main periods of time when rapid growth takes place.

  recognise that rapid growth occurs at different times in the human life cycle and identify when this happens on a growth graph

  recognise that there is a wide variation in the development of children

  present data about height in an appropriate chart or graph

   Many pupils are sensitive about their weight. Sensitivity is needed with height because a small but significant number of children have growth problems. Height/weight charts used by health professionals illustrate the range of expected heights and weights. These can be used to reassure pupils at the extremes of the range.

   Teachers will be aware of the need for sensitivity to pupils who may mature earlier or later than the majority of their peers.

   that cell division and increased cell size lead to growth of the body

   about the importance of sample size in obtaining reliable evidence

   to decide on an appropriate graph to display data

   to interpret class data and compare with national data

   Remind pupils of their work on cell division. Discuss growth and how pupils should measure it, eg weight gain, height changes, girth. Pupils explore the range of heights in the class and present their data. Help pupils to think about how many individuals are needed for measurement to ensure reliable information, what other factors should be considered, eg boys/girls, and how they will present their data.

   Discuss with the pupils trends in the data. Show charts and graphs to illustrate the range of expected heights and weights at this age. Help pupils compare the ranges shown by the charts with the data collected by the class and discuss reasons for similarities and differences in terms of sample size.

  explain that measurable changes in growth result from cell division and increased size

  suggest reasons for differences between class and national data and explain in terms of sample size

   The focus is on collecting reliable information, but pupils may need support in constructing appropriate graphs and bar charts. The activity offers an opportunity to use ICT.

   Extension: pupils could use secondary data, eg evidence from great-grandma’s height, Tudor beds, historical and literary evidence of people’s diet, Saxon burial sites, to compare growth of young people today with those in historical times when many children were not well nourished. In medieval times shortages in food supply contributed to smaller stature. However, many dark-age burial sites show that men and women had similar stature to people of today.

   Extension: pupils could also explore present-day variations in stature between countries and within the UK.

    KS3 Biology How do humans change as they grow? (Cont.)

   that changes in hormone concentrations result in the development of secondary sexual characteristics and emotional changes at puberty

   to collaborate with others to share information and ideas, and solve problems

   to answer questions using relevant evidence or reasons

   Discuss how external adult features change during puberty, eg breasts, wider hips, facial and body hair, voice changes, stronger body smell. Explain that circulating hormones cause the development of secondary sexual characteristics and reproductive organs.

   Challenge the pupils to provide evidence about whether emotional maturation during adolescence proceeds at the same rate as physical maturation in puberty, eg by selecting or modifying personal problems from a teenage magazine or by creating stories about secondary sexual characteristics or emotional maturation. Ask pupils to discuss scenarios in groups and then produce and present a reply to the rest of the class.

  recognise that reproductive organs mature during puberty as a consequence of growth and circulating hormones

  describe the observable changes of puberty in males and females, eg breasts, more body hair, different body shape

  provide examples of how physical and emotional development proceed at different rates

  share information and discuss ideas

   Reassurance about the range of different secondary sexual characteristics can alleviate pupils’ concerns and sensitivities about their stage of development.

   Extension: pupils could be given information about research into boys’ and girls’ views about parenting and discuss differences between the genders.

    KS3 Biology Reviewing work

   to bring together information about a particular aspect of reproduction

   to distinguish between the main ideas in the unit

   Provide pupils with a series of statements about the human life cycle, the processes of fertilisation, embryo development and birth, and about the specialisation of cells. Ask pupils to sort the statements into groups and use them to make summaries of the ideas encountered in the unit.

  produce summaries which are appropriately sequenced to show key ideas

  distinguish between aspects of reproduction, eg fertilisation and gestation

   It may be appropriate to give some pupils statements in one category first and then extend the work.

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Doc Brown's Revision  KS3 Science - KS3 Biology  Unit 7C Environment and feeding relationships

KS3 Biology About the unit

In this unit pupils learn:

  how habitats vary

  how plants and animals are adapted to live in a particular habitat

  how plants and animals interact with their environment and with each other, including feeding relationships

  about adaptations for feeding

  how to link food chains to make webs

In scientific enquiry pupils:

  consider the importance of sample size

  make measurements of environmental changes and interpret these

  survey the variety of living things within a habitat

  investigate the activity of a small invertebrate, taking into account variables they cannot control

KS3 Biology Where the unit fits in

This unit draws on ideas developed in the key stage 2 programme of study. It builds on unit 4B ‘Habitats’ and unit 6A ‘Interdependence and adaptation’ in the key stage 2 scheme of work.

Together, this unit and unit 6A ‘Interdependence and adaptation’ in the key stage 2 scheme of work could be used as a bridging unit.

The unit provides a foundation for unit 8D ‘Ecological relationships’ and for unit 9A ‘Inheritance and selection’.

The energy transfer ideas of unit 7I ‘Energy resources’ are used in considering feeding relationships between organisms. If this unit is covered before unit 7I ‘Energy resources’, then the treatment can be restricted to using the label ‘energy’ for what is transferred. If unit 7I ‘Energy resources’ is covered first, then links can be made to the burning of fuels and foods and the Sun as the energy resource for plants.

There are opportunities for pupils to make presentations about, and take measurements in, the environment. This links with unit 3 ‘Processing text and images’ and unit 7 ‘Measuring physical data’ in the ICT scheme of work.

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: make a series of measurements of environmental variables appropriate to the task; identify a question to investigate about the activity of an invertebrate, suggesting a suitable approach and sample size; use their results to relate animal and plant activity to environmental changes

some pupils will not have made so much progress and will: make measurements of environmental variables appropriate to the task and make suggestions about investigating the activity of an invertebrate

some pupils will have progressed further and will: describe, in terms of approach and sample size, how strongly any patterns or associations identified are supported by the evidence

in terms of life processes and living things

most pupils will: identify differences between different habitats and relate these to the organisms found in them; describe ways in which organisms are adapted to daily or seasonal changes in their environment and to their mode of feeding; describe food chains within an environment and combine these into food webs

some pupils will not have made so much progress and will: identify differences between different habitats and describe how familiar organisms are suited to the habitat in which they are found; describe some simple food chains

some pupils will have progressed further and will: explain why a variety of habitats is needed in a community; describe how different organisms contribute to the community in which they are found and relate food chains to energy transfer

KS3 Biology Prior learning

It is helpful if pupils:

  know that different habitats support different plants and animals and have identified ways in which plants and animals in a particular habitat depend on each other

  have explored local habitats to establish the variety of living organisms within them

  know that some animals feed on other animals and some feed on plants

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity. In this unit pupils:

  plan and carry out their own investigation

  collect and handle small invertebrates

  work in an outside environment

Many employers have specific guidance on fieldwork. Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  words and phrases relating to feeding, eg predator, prey, food web

  words and phrases relating to seasonal changes, eg migration, hibernation, overwintering, dormant, insulation, climatic stress

  words and phrases describing environmental conditions, eg light intensity, availability of oxygen

  words with different meanings in scientific and everyday contexts, eg producer, consumer

  words with similar but distinct meanings, eg carnivore and predator

  words relating to scientific enquiry, eg temperature sensor, sample size, reliable data

Through the activities pupils could:

  organise, sequence and link what they say so listeners can follow it

  find information from secondary sources using contents, index, glossary, key words or hotlinks

  join ideas within sentences using links of cause (so, because, since)

KS3 Biology Resources

Resources include:

  sensor and software for temperature, oxygen, light, pH measurement

  secondary sources, eg photographs, video clips, preserved and live specimens, showing predators and prey

  pictures showing the range of organisms found in a variety of habitats

  secondary sources providing information about how animals deal with seasonal changes in their environment

  secondary sources showing how some plants, eg holly, nettles, bracken, have defence mechanisms

  simulation software illustrating changes in populations

  secondary sources, eg CD-ROMs, videos, illustrating diets of animals

KS3 Biology Out-of-school learning

Pupils could:

  visit other habitats, eg nature reserves, nocturnal houses in zoos and nature centres

  find out about the feeding requirements of a variety of species of animal

  attend evening or early morning activities, eg bat watching, snake spotting, moth spotting and listening to the dawn chorus run by country parks, waterways and other organisations

  watch wildlife programmes on video and television, read accounts of life in a habitat supporting different plants and animals

  look for plants and animals in their immediate locality, eg on the way to and from school

  find out about wildlife conservation projects or ecology centres in their locality

  search the internet for information about habitats and feeding relationships using key words, eg zoo, food chain, habitat

KS3 Biology How does the environment influence the animals and plants living in a habitat?

   that different habitats have different features

   that different habitats support different organisms

   that the distribution of organisms in different habitats is affected by environmental factors,
eg light, nutrients or water availability

   to organise, sequence and link what they say so listeners can follow it

   Ask pupils about environments or habitats they studied at key stage 2 and explain that in the first part of the work in this unit they are going to look at features of habitats.

   Provide pupils with stimulus material, eg video of the Arctic, poster of woodland life, picture of cacti in a desert, underwater scene, worms in a wormery. Ask the pupils to describe the physical features of each habitat and identify major environmental factors, eg light intensity, oxygen availability, temperature range.

   With pupils, decide on a limited list of animal and plant species for each habitat. Remind pupils of the importance of making sure listeners can follow their argument, and ask them, in groups, to use secondary sources to investigate how species are adapted to life in one habitat and to present their findings, eg orally, using overhead transparencies (OHTs) or flip charts.

  identify features, eg light, temperature range, which are different in different habitats

  describe adaptations to life in a variety of habitats such as:

    – water, eg streamlined shapes help animals move through the water, water plants float or have long stems to reach surface waters

    – underground, eg streamlined shapes, adaptations for tunnelling, poor sight but good senses of smell and vibration

    – woodland, eg colour vision, climbing plants and camouflage, early growth and flowering before the canopy develops

  pick out appropriate adaptations and explain clearly their significance

  make an oral group presentation of their findings

   This activity is intended to help teachers find out what pupils know about habitats and how organisms are adapted to them. Teachers will need to take this into account in later work.

   Pupils may need help to stay focused on the question of adaptations to the habitat and help in selecting appropriate material from a large quantity of general information on the lives of particular plants and animals.

   This unit includes work on seasonal changes. It is useful to have a log of species sighted in the school and its surroundings. If possible, encourage pupils to note vegetation and other changes in the school environment over the academic year.

   Extension: pupils could explore a wider variety of habitats through
an interactive field trip,
eg www.field-guides.com

 

KS3 Biology How do environments vary?

   that some animals are adapted to daily changes in their habitat

   how to measure and record changes in environmental factors

   how to interpret patterns in data

   Ask pupils to predict how physical environmental factors around the school, eg light intensity, temperature, humidity, noise levels, would change over a 24-hour period and how they could measure the changes. With pupils, set up instruments, eg datalogging equipment with a light probe, automatic weather station, temperature and sound sensors, to monitor changes. Provide pupils with data about environmental changes around the school over a 24-hour period and help them to describe what these show and to identify links between the different changes.

   Ask pupils to suggest how the population of plants and animals in the school habitat would change over the same time, eg crows and starlings visiting dustbins in daylight, squirrels visiting after school finishes, foxes after dark; slugs, cats, mice, bats active at night. Using their ideas, secondary sources and first-hand observation where possible, help pupils to generate comparative lists of animals active during the day, at dawn and dusk and those which are nocturnal.

  describe changes in physical environmental factors, eg temperature, light intensity, over a 24-hour period

  interpret data about daily changes and explain in simple terms, eg beginning to get dark

  relate changes in variables, eg light and temperature, to each other

  relate plant and animal activity to environmental changes

   There is an opportunity to use
datalogging equipment. Secondary sources, eg newspapers, Ceefax and geography weather stations, could be used to confirm readings.

   Schools near the coast and by tidal rivers have an opportunity to focus on adaptations to changes in these habitats.

   Schools with CCTV may be able to monitor animal activity at night.

   how to frame a question to be investigated

   how to decide what factors are relevant to a question

   about the importance of sample size

   to consider results in relation to the sample used

   Using observations of small invertebrates in the school grounds or elsewhere, ask pupils to generate a suitable question about how the activity of an invertebrate, eg woodlice, snails, brine shrimps, daphnia, varies with environmental changes, eg dampness, light/dark, and to plan and carry out an investigation.

   Help pupils to produce an account of what they did, focusing on the size of sample they used, the factors they could and could not control and how confident they were in their results.

  identify a suitable question for investigation

  identify and control relevant variables

  choose an appropriate way of obtaining an adequate sample

  explain why they are, or are not, confident in their results, eg 18 out of 20 times the snails went to the damp, I think this is sufficient; we only used 6 woodlice and 4 of them chose the dark, I think we need to use more than 6 woodlice to be sure

   Extension: pupils could find out about adaptations to daily changes in two or three plant or animal species.

   If any animals are brought into the classroom, ensure that they are treated carefully and that they are returned to the habitat from which they came as soon as possible.

Safety

– teachers will need to check pupils’ plans for health and safety before practical work begins

– wash hands after handling animals. Particular pupils may have allergies and these should be appropriately taken into account. Wipe benches with disinfectant

 

KS3 Biology How do environments vary? (Cont.)

   how some animals are adapted to seasonal changes in their habitats

   that adaptations may be to avoid climatic stress

   Provide pupils with overwintering structures or photographs or video clips of these as stimulus material, eg onion bulb, pupa, twig with buds, carrot, plastic bag of hair from a moulting pet. Ask pupils to suggest when they would normally be found and their function. Show videos of habitats at different times of the year and ask pupils to identify differences and describe the consequences of these for the organisms in the habitat. Ask pupils to describe from their own knowledge how plants in the school habitat change over the year and predict the likely effects of the changes on the animals in the locality.

   Provide pupils with key words and phrases, eg migration, hibernation, overwintering of pupae, dormant structures, making food stores, thicker insulation, and ask pupils to use secondary sources to find out about these and how they help animals avoid climatic stress. Ask pupils to describe what they found out and help them to contribute to a summary sheet about seasonal changes.

  identify ways in which habitats vary through the year

  describe some strategies which plants and animals adopt to avoid climatic stress 

   It may be useful to have data about temperature ranges and daylight hours in the locality of the school to support this work.

   Some dormant twigs can be frozen successfully for use at other times of year. Ash trees are usually among the last to come into leaf.

KS3 Biology Checking progress

   to summarise and make connections between key ideas about adaptation to a habitat

   Provide pupils with a list of adaptive animal and plant characteristics and ask them to decide on the six most important for a particular habitat. Ask them to explain their choices and ask others to evaluate these critically, identifying the advantages the adaptation gives the organism. Help pupils to use the results of the work to make generalisations about adaptation.

  identify adaptations for particular habitats

  explain the advantages adaptations give an organism

 

 

KS3 Biology What is a feeding relationship?

   that animals have features which are adaptations against predators

   that animals are adapted to their particular food source

   to collect sufficient data to reduce error and obtain reliable evidence

   Review pupils’ knowledge of predators and prey by providing stimulus material, eg posters, photos, pictures, video clips, preserved and live specimens, of predatory animals and prey species, eg eagle, dog, pike, bat, spider, rabbit, antelope, snail, and asking pupils to describe how the predators are adapted for finding, catching and killing their prey and how prey species are adapted for detecting and avoiding predators. Help pupils construct tables of general features of predators and prey, eg predators may have eyes forward, acute vision and sense of smell, sharp claws/talons/beaks for piercing and tearing, may ambush or hunt by stealth, whereas prey may have eyes at the side, acute hearing and sense of smell, be easily startled, be nocturnal, camouflaged.

   Ask pupils to investigate the effect of beak shape in seed-eating birds, eg by using blunt and fine-pointed forceps to pick up and transfer seeds of varying sizes from a dish in one minute. Discuss with pupils how much data they need to gather for reliable conclusions.

  identify predators and prey from information about commonly encountered animals

  identify features of predators, eg a hooked beak, sharp claws, acute vision, ability to trap prey

  identify features of prey animals, eg camouflage, acute senses, armour, speed

  state how many observations they made and explain why this was appropriate

   Nature centres, botanical gardens and zoological collections may have outreach teachers who can bring a selection of plants and animals into schools to illustrate adaptations to habitat and food source. In addition, they often have education programmes to support visits to their establishments.

   Alternatively, pupils could use dough coloured with food dyes, or red and green wool, distributed on a marked-off stretch of grass to investigate the effectiveness of camouflage.

Safety  

– wash hands after handling animals. Particular pupils may have allergies and these should be taken into account. Wipe benches with disinfectant

 

KS3 Biology What is a feeding relationship? (Cont.)

   about characteristics of predator and prey species

   to join ideas within sentences using links of cause, eg so, because, since

   that all the organisms in a habitat can be linked together in food webs

   that food webs are made up of a number of food chains which start with plants

   that arrows in a food chain represent energy transfer

   Establish by quick questions pupils’ understanding from work in key stage 2 of terms related to food chains, eg producer, consumer.

   Present pupils with stimulus material, eg a habitat poster such as meadowland or woodland, and challenge them to make as many food chains as they can. Ask them to identify producers, consumers, herbivores and carnivores. Explain the direction of the arrows in the food chain and relate to energy transfer, with the Sun as the ultimate source of energy. Ask pupils to write a sentence about each food chain, using links of cause, eg so, because, since.

   Ask pupils to find examples of animals that occur in more than one food chain and to explain what this shows about their food sources. Show pupils a food web and explain that it is a more accurate representation of feeding relationships.

   Help pupils use the food chains they have generated to construct a food web for display. Provide pupils with secondary data so they can practise identifying food chains within a food web and constructing food webs from food chains.

   Establish with pupils that food webs, food chains and terms, eg predator and prey are ways of describing feeding relationships.

  sort organisms into a food chain

  explain what is meant by, and identify, carnivore, herbivore, consumer, producer

  identify food chains within food webs and describe what a food web shows

  explain the direction of arrows in a food chain,
eg energy from the leaves passes to the caterpillar

   In unit 7I ‘Energy resources’, the idea that food chains show energy transfer is introduced.

   Food chains may also start with bacteria or fungi. However, at this stage it is acceptable for pupils to be taught that food chains begin with plants.

   Pupils do not need to be familiar with the term ‘trophic level’ at this stage.

   Extension: pupils could be asked to find out about different predators and prey and produce an account of how one of each is adapted.

 

KS3 Biology What do food webs tell us?

   to make careful observations of plants and animals and sources of evidence about animals’ food

   to link organisms together in food webs

   that some plants have adaptations to deter animals from feeding on them

   to interpret evidence about food sources and draw conclusions from it

   Ask pupils to suggest likely places to find plants and animals in the locality of the school, what species they think they might find and how the plants and animals might be linked in food webs. Encourage pupils to consider what evidence we use to find out what animals eat, eg owl pellets, remains near lairs and nests, thrush anvils, observations, teeth marks, bird droppings showing coloured berries have been eaten.

   Show pupils how to use simple equipment and techniques, eg direct observation, pooters, tree beating, and ask them to find, identify and record as many species of plants and animals as possible within the school locality.

   Ask pupils to record any observations which help to identify a food source, eg a greenfly found on a rose bush, woodlice found under decaying wood, fly entangled in a spider’s web, and to note plant features which may deter animals from feeding on them, eg prickles on holly, thistles, sting on nettles. If appropriate, extend this work using secondary sources.

   Help the pupils to use the information gathered to construct a database using a data-handling programme.

  identify plants and animals found in the immediate locality

  state that a wide variety of organisms is found in quite small habitats

  describe and explain what might provide evidence about animals’ food

  identify features of plants which may deter animals from feeding on them

  interpret evidence about food sources, eg the bird droppings are purple, so they could have eaten blackberries

   This exercise can be done in very
small-scale habitats, eg flower bed, grass verge. It needs to be clear that the focus of the activities is identification of food webs, because pupils may have visited an area local to their school in key stage 2 to identify organisms, using keys, and to identify food chains.

   Pupils are likely to be familiar with using keys to identify living things from their work at key stage 2. Some may need more practice.

   It is not necessary to quantify species at this stage, but it may be useful to count the number of species identified and the number of individuals of different feeding types for possible use in year 8.

   If any animals are brought into the classroom, ensure that they are treated with respect, their needs are met and that they are returned to their habitat as soon as possible.

Safety

all off-site visits must be carried out in accordance with school/LEA guidelines

– pupils should wash their hands after handling animals and soil.
Particular pupils may have allergies and these should be taken into account. Dis­infect pooter mouthpieces

 

KS3 Biology What do food webs tell us? (Cont.)

   that all the organisms in a habitat can be linked together in food webs

   to find information using contents, index, glossary,
key words or hotlinks

   Provide pupils with secondary sources, eg reference books, CD-ROMs, databases, to find information about the diet of animals identified in the previous activity, and remind them how to use the index, contents section, key words and hotlinks. Ask them to add the information to the database. Ask them to use the information to construct food chains using the species identified, and to describe what the food chains show. Help the pupils to link their food chains together into a food web. Challenge the pupils to explain any missing links, eg absence of carnivores, such as owls or hawks. Help pupils to produce a display of their food web(s).

 

  use organisational features of text to identify relevant information about the diet of animals

  place food chains within a food web

  describe how all the organisms in a habitat can be linked together in food webs

  sequence a food chain

  recognise that arrows in a food web or food chain show the direction of energy flow

   Pupils may need reminding that food webs are the focus of the activity, as they may have found out about the food source of a local animal in key stage 2.

   Pupils often have difficulty with the idea that arrows in a food chain represent energy flow. This could be reinforced here.

   that factors influencing the number of organisms in one part of a food web have an effect on other parts of the web

   Challenge pupils to suggest where there is competition between species in the food web. Reinforce their ideas by removing a plant species or adding two or more consumers and ask the pupils to predict the consequences.

   Extend the work by asking pupils to use food webs, eg those generated in previous activities, to practise predicting the effects of altering the numbers of various organisms in a web. Use ICT simulations to test out the predictions made.

  predict the effects of altering the numbers of an organism in one part of a food web

  recognise that organisms living in a habitat compete with each other for food resources

  recognise the importance of plants as the food source at the start of all food chains

   This activity provides opportunities to use ICT simulations.

KS3 Biology Reviewing work

   that organisms in a habitat compete for resources from the environment

   Construct a paper and wool model of a food web identified in the previous activity. Remove one animal species from the web, eg by cutting the strands of wool holding it in place. Ask the pupils what will happen to the animals that feed on that species. Challenge pupils to identify any other effects on the food web.

   Extend by providing pupils with a food web in which at least one animal is a seasonal visitor and asking them to identify differences in the food web in other seasons.

  predict and explain the consequences of changes in the organisms making up a food web

   If the food webs generated earlier are very complex, it may be better to simplify them for this activity.

   As an alternative, pupils could be given copies of a food web generated earlier, with an animal blanked out.

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Doc Brown's Revision  KS3 Science - KS3 BIOLOGY Unit 7D Variation and classification

KS3 Biology About the unit

In this unit pupils:

  explore variation within and between species

  consider why classification is important and are introduced to scientific classification of animals

  investigate patterns of variation in living things and ways of representing and explaining the occurrence of variations

In scientific enquiry pupils:

  frame questions to be answered using first-hand or secondary data

  make qualitative observations and record these in a variety of ways

  draw conclusions from observations and explain these using scientific knowledge

  investigate variation between individuals of the same species using an appropriate sample size

Much of this work involves the interpretation and analysis of visual information gathered from a variety of sources. The use of enlarged images and other methods of gathering information may support learning for pupils with visual impairment.

Teachers will be aware of the need for sensitivity to the circumstances of pupils and their families throughout this unit.

KS3 Biology Where the unit fits in

This unit draws on ideas developed in the key stage 2 programme of study. It builds on unit 5B ‘Life cycles’ and unit 6A ‘Interdependence and adaptation’ in the key stage 2 scheme of work, and on unit 7C ‘Environment and feeding relationships’.

It provides a foundation for unit 8D ‘Ecological relationships’ and unit 9A ‘Inheritance and selection’.

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: use observation to identify questions to investigate about variation between individuals; suggest data to collect to answer the questions; present and analyse the data; identify associations or correlations in their data

some pupils will not have made so much progress and will: make suggestions about data to be collected to answer questions about variation and, with help, present data using ICT and identify patterns or associations

some pupils will have progressed further and will: evaluate graphs and tables of data in relation to sample size and describe how strongly any association or correlation is supported

in terms of life processes and living things

most pupils will: identify similarities and differences in organisms of the same species and begin to attribute these to environmental or inherited factors; explain the importance of classifying living things; identify some of the main taxonomic groups of animals and describe some features of these

some pupils will not have made so much progress and will: identify similarities and differences between organisms of the same species and classify organisms into plants and animals; identify a few taxonomic groups of animals

some pupils will have progressed further and will: recognise that inherited and environmental causes of variation cannot be completely separated; name some organisms which are not readily classified as plant or animal

KS3 Biology Prior learning

 It is helpful if pupils:

  know how to identify different living things

  can name the parts of living things

  know how to use a key to identify an unknown living thing

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity. In this unit pupils:

  handle small invertebrates

  work in an outside environment

Many employers have specific guidance on fieldwork. Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  words relating to the structure of organisms, eg segment, abdomen, shell

  words with similar but distinct meanings, eg limb and leg

  words and phrases relating to classification, eg vertebrate, invertebrate, mammal, amphibian, reptile, feature, characteristics, taxonomic group

  the words variation, classification, identification, inherited, environmental

  words relating to scientific enquiry, eg classify, association, correlation, confidence, spreadsheet, database

Through the activities pupils could:

  spot connections and links between how information is presented in different forms

KS3 Biology Resources

Resources include:

  secondary sources to explore environmental and inherited variations, eg illustrations of environmental variation, family photographs, other reference literature

  photographs showing different animals within one species, eg dogs, cats

  database and spreadsheet software

  secondary sources containing descriptions of living things, eg novels, poems, field guides

  secondary sources to explore the variety of living things, eg CD-ROMs, photographs, video clips, other reference literature

  preserved specimens of animals representing major taxonomic groups

  suitable living animals for observation

  prepared sheets of 30 fingerprints

  data sheets on leaf size

KS3 Biology Out-of-school learning

Pupils could:

  observe animals found in the garden or home, including pets

  visit a library to find out more about different groups of living things, as well as extinct groups such as the dinosaurs

  visit a museum, zoo, botanical garden or fishery to observe a wider selection of living things

  use the internet to find out more about the variety and classification of living things, eg www.nhm.ac.uk/

  watch wildlife programmes

  find out how clothes manufacturers take account of size variations

    KS3 Biology How do individuals of the same species differ from each other?

   that individual members of a species may differ in many ways

   to use a spreadsheet to store data

   to frame questions which can be investigated

   to interpret graphs generated by a spreadsheet

   to decide how confident they are in the evidence

   Show pupils photographs of a variety of animals of a species, eg dogs, cats, and ask them to point out the differences between them. Extend to humans and elicit examples of differences.

   Collect the data, eg eye colour, height, arm span, hand span, about individuals, eg members of the class, relatives, on a spreadsheet. Show pupils how to use the spreadsheet to produce graphs of variation for particular features.

   Ask them to suggest and to investigate correlations, eg Do taller pupils have wider arm spans? by producing and interpreting graphs and presenting their findings.

  suggest ways in which species, eg dogs, humans, differ from each other

  enter information into a spreadsheet

  use a spreadsheet to draw graphs

  frame questions which can be answered using a spreadsheet

  interpret graphs generated by a spreadsheet and say how strong they think an association or correlation is, eg most of the taller people have wider arm spans, but it’s not always true

   Teachers will be aware of the need for sensitivity towards some pupils who may not wish to provide personal information and of the need to help pupils to be sensitive to the differences between them.

   Pupils may have investigated associations in key stage 1 or 2. This activity is intended to review that work and take it further, by showing the range of questions that can be investigated using a prepared database and the range of graphs that can be produced and interpreted.

   As an alternative, the data could be used to create a branching database which pupils could use, eg a game in which pupils have to guess the identity of a mystery person, given bits of information about them.

   KS3 Biology How do individuals of the same species differ from each other? (Cont.)

   to frame questions that can be investigated

   to choose a sufficiently large sample size

   to interpret graphs and draw conclusions from them

   to decide how confident they are in the evidence 

   Extend the idea of variation between individuals to other animals and plants. Ask pupils to observe different individuals of the same species, eg daisies, snails, holly bushes, to identify differences between them and then to frame a question which can be investigated, eg
– Do pink-tipped daisies have longer stems?
– Do snails with longer shells have wider shells?
– Do longer holly leaves have more prickles?

   Help pupils to decide how to collect data and decide on a suitable sample size. Ask them to produce a report of their investigation, encouraging the use of a spreadsheet for the analysis of data.

  suggest a question to be investigated based on their observations and decide what measurements or observations are appropriate

  choose a sufficiently large sample to be confident in their conclusions

  interpret their graphs and say how strong they think an association or correlation is

   If animals are brought into the classroom, ensure that they are treated with care and returned to the habitat from which they came as soon as possible.

   There are many questions of this kind that pupils can investigate, eg through fieldwork or studying a collection, such as shells. What is chosen will depend on the school’s location, resources and surroundings.

Safety

wash hands after handling animals and wipe bench with disinfectant

– if off-site visits are made, these must be carried out in accordance with school/LEA guidelines

– pupils’ plans must be checked for health and safety before practical work begins

    KS3 Biology What are the causes of variation?

   that some characteristics are inherited

   that although individuals are like their parents they are not identical to them

   that offspring from the same parent show considerable variation

   Provide pupils with information relating to variations between members of different generations of a family. Ask them to identify patterns of similarities which suggest real or fictional inherited features and ask them questions, eg What features are inherited in their own families?

   Challenge them to consider why some members of the family share common features that may not be shown by other members. Establish that this may be because inherited characteristics were not passed on from parent to offspring or that there are other causes of variation.

  identify characteristics, eg eye colour, skin colour that are inherited

  identify examples of patterns of similarities and differences within several generations of one family

  suggest reasons why differences and similarities exist within families

   Sensitivity to issues relating to parenthood is needed when talking about inheritance. Teachers may prefer to use a fictional family for this work.

   Information on family characteristics may be presented as photographs of members of the same family.

   Some pupils may continue to think that boys inherit characteristics from their fathers and girls from their mothers.

   Mechanisms of inheritance and selective breeding are covered in unit 9A ‘Inheritance and selection’.

   that some variations are inherited

   how environmental differences can result in variations in a species

   to interpret secondary data and draw conclusions from it

   Show pupils photographs or other secondary sources of information illustrating variation related to environmental causes, eg trees grown in windy and non-windy environments, gentian plants growing above and below the snowline, healthy and undernourished children, and then ask pupils to review their work on variations within a species and to consider the causes and origins of the variations.

   Ask pupils to think about their own observations of animals and plants and to suggest ways in which the environment might cause variations between individuals.

   Present pupils with data, eg nettle leaf size in sunny and shaded positions, dog-whelk shell size on sheltered and exposed shores, and ask them to suggest why the variations occurred.

  identify some characteristics that are inherited, eg hair colour, eye colour, colour of flower, shape of leaf

  suggest ways in which environmental difference may result in variation within a species, eg length of leaf, height of plant, weight, explaining how the data supports their conclusions

   It is important to establish that some variation, eg height, may be a result of both inherited and environmental factors.

   As an alternative, pupils could be presented with blackberry leaves from open and shaded habitats and asked to work out leaf areas and suggest why variations occur.

   KS3 Biology Checking progress

   to present ideas about causes of variation

   Summarise ideas about variation and inheritance by asking pupils to write an account, possibly as a poem, about their own or a fictional family. They could write about the different individuals, describing features which have been inherited, and others which are the result of environmental effects.

  describe the inherited and environmental differences in a group of individuals

   Teachers will be aware of the need for sensitivity to the circumstances of some pupils. Teachers may prefer to use a fictional family for this work.

   Responses of different kinds could be used in the next activity where pupils are asked to compare different styles of writing.

    KS3 Biology How can we describe living things?

   to compare different styles of writing about observations

   to spot connections and links between how information is presented in different forms

   Remind pupils that the work they have done so far in this unit has focused on variation within a species and explain that they are now going to think about differences between species.

   Present pupils with written descriptions of animals or plants taken from a variety of sources, eg field guides, poems, novels, and ask them to suggest what animal is being described. Discuss the different ways of observing and presenting this type of information.

  comment on the use of different styles of writing which may be used to describe living things

  suggest why a particular style is used in a text

   In this activity prose or poems could be compared with the more factual scientific descriptions of living things found in identification keys and field guides.

   CD-ROMs and video clips could be used to observe a variety of animals and plants in motion.

   how to make sure they are working safely with living organisms

   to make and record appropriate observations relevant to a particular piece of work

   to use observations to make comparisons of living things

   Explain the safety procedures to be followed when working with living things, including consideration of the welfare of the specimen.

   Provide a range of living things, eg snail, earthworm, fish, hamster, and secondary sources and ask pupils to make observations to identify differences, eg what the specimen looks like and how it behaves, and to record these in appropriate ways. Ask pupils to work in pairs or small groups to produce a piece of writing about an animal or a pair of different animals.

   Ask pupils to suggest appropriate observations to make, and features to record, from the range of specimens provided. Encourage, through questioning, suggestions of observations which could be tabulated, eg number of legs, colour, segmented body or not, and provide a suitable table for collation of observations.

   Make sure pupils are familiar with the terms for parts of animals’ bodies. Ask pupils to make observations of a number of specimens and to record these using the table. Discuss problems arising from observations, eg Do different pupils’ records for one specimen agree?

  handle living organisms in a safe and appropriate manner

  make suggestions about the characteristics to be observed and recorded

  make appropriate observations of a range of specimens and record these

  describe the similarities and differences between two living things

  use scientific vocabulary to describe the body parts of animals

   This activity is intended to help teachers find out about pupils’ experiences, and knowledge and understanding of living things. Teachers will need to take this into account in their short-term planning of later activities in this and other units.

   If animals are brought into the classroom, ensure that they are treated with care and returned to the habitat from which they came as soon as possible.

   A range of living specimens could include those that may be easily collected from and returned to the local environment, eg snail, slug, woodlouse. These could be supplemented with images, eg photographs, CD-ROMs, internet or videos.

   The information recorded here is to be used to classify living things in the next activity.

   Sometimes pupils’ observations of the same specimen will be different. This will provide an opportunity for discussion of issues relating to reliability.

Safety

– wash hands after handling animals and wipe bench with disinfectant

    KS3 Biology How can we sort things into groups?

   that although individual members of a species differ in many ways they have features in common

   to classify fingerprints into groups which have features in common, giving reasons

   Ask pupils what they know about fingerprints and how they are used. Establish that they are used to identify individuals because they show great variation, but they can be classified because they have common features.

   Provide pupils with a sheet on which there are 30 fingerprints from 20 to 30 different individuals. Ask the pupils to observe these closely and to work in groups to devise their own system for classifying them into groups with features in common, giving their reasons. Once this has been done ask them to find differences that might be used to identify individuals. Present them with a single fingerprint and ask them to identify which person from the original set it belonged to.

   Use the fingerprint example to help pupils understand that although there is variation between individuals, there are sufficient similarities, eg among members of a species, to allow them to be recognised as one group.

  suggest ways in which fingerprints differ from each other

  classify fingerprints into groups which have features in common

  suggest reasons for the groups which they have made

  use their classification to identify an unknown individual

   Fingerprints can be classified into three general groups: loops, arches and whorls. However, some pupils may identify further distinguishing features and produce five groups: loop, simple arch, whorl (symmetrical), whorl (spiral), whorl (double loop).

   The original sheet may be enlarged for inspection, or hand lenses may be used for observation.

   There is an opportunity to invite a representative of the police force to talk to pupils about how fingerprints and other techniques are used to identify individuals.

   to sort organisms into groups according to common features

   that there are different ways of classifying living things

   that newly discovered organisms may fit into an already existing system of classification or extend it

   Provide pupils with the data collected in their review of organisms. Ask them to use this data to sort the organisms they studied into sets, with common characteristics, and to give the reason for their groupings. Ask groups to report back on their rationale for grouping and highlight different groupings which emerge from this activity. Help pupils to consider the advantages and disadvantages of different systems, and to comment on this.

   Present pupils with information on a new organism, eg as a photograph, and ask them to place this into one of their existing groups. Make this challenging by selecting an organism which will cause conflict between two groupings in the classification, and may force pupils to reconsider and reclassify their initial groups.

   Review the outcomes by asking pupils to produce a display of their classification.

  sort living organisms into groups and suggest reasons for the groups chosen

  evaluate the relative advantages of methods used to classify organisms

  review their own classification in the light of evidence presented by new observations

   Pupils may initially group organisms according to features which are not particularly helpful, eg live in water, live on land, live in air, or have legs, have wings, have neither. Challenge such groupings by guiding pupils to see that some organisms could be in two groups at once, and ask them to reclassify so that this cannot happen.

   Extension: the data collected could be entered into a tree database programme, which pupils can use to classify specimens.

    KS3 Biology How do scientists classify living things?

   that scientific classification is important because it is a worldwide labelling system, and provides a means for systematic study of living things

   that two groups of living things are green plants and animals

   that animals can be subdivided into vertebrates and invertebrates

   that vertebrates include mammals, birds, fish, reptiles, amphibians

   Describe using secondary sources, eg photographs, video clips, the early attempts made by scientists to classify living things into groups, and ask pupils to suggest reasons why an agreed system for worldwide use is helpful. Explore knowledge and understanding of the major groupings of living things, eg plants and animals.

   Explain the hierarchical nature of classification by introducing the notion that large groups, eg animals, can be subdivided into smaller subgroups, eg invertebrates and vertebrates. Introduce the major subgroups of vertebrates and ask pupils to describe the common features within each group.

   Provide pictures of a range of animals for pupils to classify into these groups, and ask them to present their work as a branching diagram.

  explain some of the advantages of the scientific classification system

  describe some features of animals and plants

  summarise the features that groups of vertebrates have in common

  classify animals as invertebrate or vertebrate and as one of the main vertebrate groups

   Pupils often have difficulty in being consistent in their classification, eg they may classify a mouse as a mammal, but say it is an invertebrate because it can ‘squeeze through bars’ and so cannot have a backbone.

   Limit the information in this activity to the animal groups mentioned. Others are introduced in the next activity. Classification of plants is introduced in unit 8D ‘Ecological relationships’.

   Teachers may wish to introduce the ‘five kingdom’ model to some pupils.

   that invertebrates can be further subdivided

   to search a CD-ROM database for information

   to transfer written information from one form to another

   Illustrate some sets of invertebrates using a range of resources, eg photographs, videos, live animals. Ask different groups of pupils to find information, eg from a CD-ROM database, about the main characteristics of one group, and some examples. Ask them to present their findings in a succinct format to be shared with other groups.

   Ask pupils to summarise the information from each group of pupils as a table showing some main groups, their characteristics, and examples.

  give an example of one invertebrate group which can be subdivided

  find and present information about one subgroup of invertebrates in an appropriate written format

  summarise the information about some main groups in a table

   Suitable sets of invertebrates include insects, molluscs and arachnids.

   At this stage it is not necessary for pupils to distinguish between levels of subgroup, eg phylum, class.

    KS3 Biology Reviewing work

   to classify animals into the main taxonomic groups

   Ask pupils to review their original observations on a group of animal specimens, and to use what they have found out to classify each specimen as vertebrate or invertebrate and as one of the subgroups of vertebrates or invertebrates, eg insect, mollusc, arachnid.

  correctly classify animals into their taxonomic groups

   When pupils classify animals, it is helpful to provide them with descriptions of the main characteristics of groups.

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 Doc Brown's Revision  KS3 Science KS3 BIOLOGY Unit 8A Food and digestion

KS3 Biology About the unit

In this unit pupils learn:

  about different foods and how they can be combined to produce a balanced diet

  how food is broken down by digestion so it can be used by the body, for energy, growth and repair

In scientific enquiry pupils:

  consider the extent to which evidence about diet can lead to firm conclusions

  use a model to explore digestion

  use chemical tests to identify food types

  present and interpret data from secondary sources

  draw conclusions from observations and explain these using scientific knowledge

  investigate a question about nutrition using secondary sources of information

KS3 Biology Where the unit fits in

This unit draws on ideas about food and nutrition developed in the key stage 2 programme of study. It builds on unit 5A ‘Keeping healthy’ in the key stage 2 scheme of work and on unit 7A ‘Cells’.

The particle model of matter is introduced in unit 7G ‘Particle model of solids, liquids and gases’ and is revisited in this unit in the context of digestion.

The unit relates to other units that focus on life processes in humans: unit 8B ‘Respiration’ and unit 9B ‘Fit and healthy’, which revisits the concept of a healthy diet.

The energy transfer ideas of unit 7I ‘Energy resources’ are used in the context of digestion. Energy should be distinguished from ‘stuff’ (food as the energy resource or fuel).

This unit relates to unit 8A(i) ‘Exploring materials (food)’ and unit 9A(i) ‘Selecting materials (food)’ in the design and technology scheme of work.

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: use secondary sources of information to generate graphs or displays relevant to questions asked; recognise that interpretation of evidence about questions of health and diet may be difficult; identify and control relevant variables when investigating the action of an enzyme

some pupils will not have made so much progress and will: find information from selected secondary sources about food and diet; generate graphs or displays relevant to questions asked; with help, control relevant variables when investigating the action of an enzyme

some pupils will have progressed further and will: choose secondary sources to provide the information needed about food and diet; explain why interpretation of evidence about questions of health and diet may be difficult

in terms of life processes and living things

most pupils will: name nutrients, fibre and water as part of a balanced diet, identifying examples of foods in which they are found, and describe the role of the main nutrients in the body; use a model to describe how large molecules are broken down during digestion and describe the role of blood in transporting products of digestion around the body

some pupils will not have made so much progress and will: name some groups of nutrients and identify some examples of foods in which they are found; describe a balanced diet; recognise that blood transports products of digestion around the body

some pupils will have progressed further and will: explain why some nutrients have to be broken down before they can be used by the body and why some foods cannot be digested by humans

KS3 Biology Prior learning

It is helpful if pupils:

  know that food is needed for activity and growth, and that an adequate and varied diet is needed to maintain health

  know that matter, including food, consists of particles, eg molecules, which can differ in size

  recognise that food provides energy for the body

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity.  In this unit pupils:

  carry out chemical tests on a range of foods

  investigate the effect of saliva on starch

  plan and carry out their own investigation into enzyme activity

Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide.  Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  scientific words relating to the structure of organisms, eg intestine, villus

  more specialised words relating to nutrition, eg carbohydrate, protein, enzyme

  words and phrases with similar but distinct meanings, eg take in and absorb, feeding and digestion

  words that extend their vocabulary, eg absorption

Through the activities pupils could:

  show relationships between ideas by using links which show purpose, eg in order to, so that, and reservations, eg although, unless, if

  select relevant information and link to other information, from a range of sources

  distinguish facts from hypotheses/theories/opinions and consider how far information is complete and helpful

KS3 Biology Resources

Resources include:

  secondary sources to explore the constituents of food, eg diet software, CD-ROMs, dietary information leaflets, video clips of TV advertisements, other literature, which may include articles from magazines

  a range of foodstuffs for testing, sufficient to provide several samples rich in each of the major chemical groups in food, including foods that are found in the diet of other countries

  illustrative material relating to advertising claims for foods, eg from magazines

  database and spreadsheet software

  simulation software illustrating digestion and transport of substances in the blood

  a collection of food packaging, including cereal packets showing nutritional contents

  media reports, magazine, newspaper and television advertisements relating to food and diet

KS3 Biology Out-of-school learning

Pupils could:

  visit a supermarket to find out more about foods

  look at menus and labels in fast-food outlets

  read articles in magazines and newspapers about issues relating to food and diet, eg for athletes, pregnant women, very young children

  find out about conflicts in dietary advice, and world food shortages

  extend their ideas about diet during holidays and visits to other families

  use the internet to find information and advice on food and diet, eg www.nutrition.org.uk

    KS3 Biology What’s in food and why is it important?

   that foods are a source of raw materials for the body

   that foods are the energy resource to maintain the body’s activities (growth, repair and movement)

   Use a true/false quiz to assess and revise pupils’ knowledge and understanding of food and diet. Provide a selection of terms used in the quiz and ask pupils to link related terms together. These terms can be used again at the end of the unit when reviewing work to monitor progress in learning. Ask them about work carried out in key stage 2. Review the main reasons why we need food.

  identify some reasons why food is important, eg as raw material, for growth, for energy

   Teachers will be aware of the need to treat issues about diet with sensitivity, including being aware of the diet in other countries and cultures.

   This activity is designed to find out what pupils know and understand about food and diet. Teachers will need to bear this in mind in later work.

   In key stage 2, pupils are likely to have grouped similar foods together and discussed which provide materials for growth and which are more immediate sources of energy. Most pupils will not have formally classified foods as proteins, carbohydrates, etc.

    KS3 Biology What’s in food and why is it important? (Cont.)

   that foods contain a mix of proteins, carbohydrates, fats, vitamins, minerals, fibre and water

   to use chemical tests to identify proteins, carbohydrates and fats

   to work safely with chemicals

   to present results to highlight significant points

   Ask pupils to use the nutritional information panel from cereal packets to identify the main nutrients contained in food, and establish that carbohydrates, proteins, fats, fibre and water form the bulk of food.

   Demonstrate food tests to identify protein, starch, sugars, fats, and water, ensuring that pupils are aware of the health and safety requirements for these tests.

   Provide a range of foods, eg 15 samples, and ask pupils working in groups to use the food tests to identify the presence of nutrients in the foods. Help pupils to share results and produce a Venn diagram showing foods which have different combinations of the nutrients.

   Discuss with pupils the importance of water in the diet, what the sources of water are and whether it should or should not be counted as a nutrient.

  identify foods which are rich in particular nutrients

  use chemical tests to identify proteins, carbohydrates and fats

  work safely with chemicals

  construct a Venn diagram showing the combinations of nutrients in each food sample tested

   Extension: pupils could be asked to find out about how mammals in desert conditions obtain sufficient water in their diet.

Safety

– appropriate risk assessments should be made in relation to the proteins, carbohydrates and fats used and the reagents used to test for them

very dilute sodium hydroxide
(0.2 mol dm
-3
) should be used in the Biuret test for protein

Benedict’s (not Fehling’s) solution should be used in the tests for sugars

if ethanol (highly flammable) is used to test for fats, ensure no naked flames are used and remind pupils how to heat a test tube of liquid safely

pupils should not eat the food tested because of possible contamination

beware of foods containing nuts.
If pupils with known allergies are present, follow appropriate procedures after risk assessment

    KS3 Biology What’s in food and why is it important? (Cont.)

   that vitamins and minerals are present in smaller amounts than the other constituents of food

   how to search for information in databases or spreadsheets

   to frame a question that can be investigated

   to decide whether to use
first-hand or secondary data

   to use and interpret
ICT-generated graphs

   that protein is important for growth and repair and that carbohydrates and fats more commonly provide energy

   Extend pupils’ understanding of a balanced diet by providing software on diet containing information about the nutritional content of a range of foods.

   Depending on the nature of information provided, help pupils to frame appropriate questions to investigate, eg Which foods contain starch and fat?, and to use the spreadsheet to produce and interpret graphs. Ask them to compare the results obtained with the Venn diagram from the previous activity and to suggest reasons for differences.

   Help groups of pupils to use the results of their investigations to produce a summary leaflet about one type of food constituent, including information about foods that are a good source of it and the role of this food constituent in the diet.

   Bring together all the leaflets as a class booklet and establish the main role of each type of food in the diet.

  use ICT to produce graphs or displays relevant to the question asked

  use data to show that vitamins and minerals are present in foods in smaller amounts than the other nutrients

  describe, eg in an information leaflet, good sources of one nutrient and the importance of that nutrient in the diet

  identify the main role of proteins, carbohydrates and fats in the diet

   Pupils should be reminded that information is normally given in terms of 100g of food and that this may not be a standard portion. They could scale the values up or down according to the standard portions and assess the nutritional value of a typical meal. This provides an opportunity to reinforce ideas about making fair comparisons.

   Extension: pupils could use information in a database or spreadsheet to answer questions, eg

    – Are foods containing protein more expensive than other foods?

    – What are the sources of protein for a vegetarian?

    – How does the nutritional content of a prepared microwave meal compare with that of a similar freshly prepared cooked meal?

    KS3 Biology Which foods provide a balanced diet?

   that a healthy diet contains a balance of foodstuffs

   Introduce the idea that there are many different healthy and balanced diets by inviting pupils from a variety of backgrounds to describe some of the main features of their own or their family’s diet. Suggest that pupils ask senior members of their family to describe the type of diet they had when they were children.

   Use food packaging, advertising claims, media reports, or recorded television advertisements as a stimulus to raise questions, eg

    Can too much salt be harmful?

    What is a healthy diet?

    Should children and adults have the same diet?

    Are low-calorie alternatives always preferable?

    How do diets of different cultures differ?

   Raise the issue of what exactly is meant by a ‘healthy’ balanced diet.

  explain that a healthy diet contains a balance of six groups of chemicals (proteins, carbohydrates, fats, vitamins, minerals, fibre) and water

   Teachers will be aware of the need to ensure that pupils are sensitive to differences between each other’s individual diets as well as the diet of their families and friends.

   Whilst the concept of a balanced diet is easy for pupils to understand, the media present much conflicting dietary advice, which may be biased according to its source.

   Extension: pupils could find out about the special diets of other pupils and consider the reasons why the balance of constituents within these diets is different and important.

   to distinguish facts from theories/hypotheses/opinions

   to show relationships between ideas, by using links which show purpose and reservations

   Ask pupils to use information from a variety of secondary sources to find out more about one question from those already raised by pupils or others, eg

    What foods should you eat to reduce the chance of heart disease?

    What do athletes eat at different stages of training?

    What does a pregnant woman need in her diet?

    What are ‘organic’ foods and how are they different from other foods?

    Are breakfast cereals really good for you?

   Discuss with pupils what they have found out and the extent to which they have confidence in the information they used.

  critically assess the sources of secondary data, and use selected sources for a purpose

  identify factual information and distinguish it from an opinion/claim, focusing on the language used

  recognise when presenting results that knowledge is incomplete and interpretation of evidence is difficult

   This provides an opportunity for considering an area of science in which our knowledge is incomplete and interpretation of the available evidence is difficult.

    KS3 Biology Which foods provide a balanced diet? (Cont.)

   to select relevant information and link to other information from a range of sources

   to recognise where evidence is not sufficient to draw firm conclusions

   Ask pupils to produce a report of their findings and conclusions in an interesting and appropriate format, eg display work, an advisory leaflet for a particular target group, a class debate, a radio interview script.

   Remind pupils about earlier work on food chains and contrast the diet of animals with the range of the human diet.

  select relevant information

  indicate where knowledge is not sufficient to draw a firm conclusion

  represent information in a format appropriate to the audience

   Leaflets and posters providing information on diet are available from many sources, including health promotion units and health organisations, eg the British Heart Foundation, British Nutrition Foundation, food manufacturers, food marketing organisations, eg The National Dairy Council, food retailers and the media.

   Many of these organisations also provide internet sites presenting dietary information. Pupils could be encouraged to explore these.

   Extension: pupils could be asked to find out about the diet of another mammal and to compare the range of nutrients it provides with those in the human diet.


KS3 Biology Checking progress

   to generate questions about nutrients and diet

   Ask pupils to produce a quiz sheet to test knowledge and understanding about food and diet and exchange with other pupils, who can use them to assess their knowledge and understanding.

  generate appropriate questions together with answers related to the content of the unit

 

    What happens to food inside the digestive system?

   that the digestive system consists of a tube through which food passes

   to interpret the relationship between a model gut and the digestive system

   to suggest explanations for observations

   Ask pupils for their ideas about what happens to food once it has been eaten. Develop the idea that food enters a tube running through the body, and that this, and associated organs, make up the digestive system. Build up their suggestions into a sequence of events commencing with feeding, followed by absorption and ending with elimination of faeces.

   Explain that what happens to food inside this tube can be explored using a model, eg a model gut made from visking tubing filled with a ‘starch meal’; a software simulation. Ask pupils about how they tested for starch earlier and help them to test the contents of the ‘gut’ and the surrounding water for starch. Ask pupils to explain their observations and to consider the implications of nutrients from food entering the body.

   Ask pupils to interpret their findings in the light of their previous assumptions.

  describe how food passes along a digestive tube which runs through the body

  offer suggestions about what happens to food as it passes through this tube

  make links between the model gut and the digestive system

  use scientific knowledge to explain observations

   Most pupils will not have studied digestion at key stage 2, although they will have ideas about what happens to food inside the body. This unit focuses on what digestion involves and why it is necessary, rather than on the structure of the digestive system or on the detail of how and where particular foods are digested.

   The use of the model gut will allow pupils to investigate the processes going on inside the intestine, and to appreciate the importance of the process. Using a model such as a sieve with chickpeas and sand may help some pupils.

   Pupils are introduced to the particle model in unit 7G ‘Particle model of solids, liquids and gases’ and to ideas about atoms and molecules in unit 8E ‘Atoms and elements’.

    KS3 Biology What happens to food inside the digestive system? (Cont.)

   that foods contain starch, protein and fat, which have molecules that are too large to be absorbed by the body

   that sugars, vitamins and minerals are generally smaller and can be absorbed by the body

   that large molecules are broken down by enzymes in the gut to form smaller molecules, which pass through the wall of the small intestine

   how models can be used to represent and explain complex processes

   Check pupils’ understanding of the relationship between size of food molecules and ease of absorption, eg by showing them models representing molecules of starch, protein, fat, sugars, vitamins and minerals. Ask pupils which of these make up most of the foods they eat and challenge them to suggest what must happen to the large molecules. Ask them to predict which will be absorbed most easily, with reasons.

   Establish that digestion involves breaking larger molecules into smaller ones. Introduce the idea that digestion involves enzymes which act on large, insoluble molecules to break them down into smaller, soluble molecules. Help pupils to set up a model gut containing saliva and starch, and to test the contents of the water for sugar and the contents of the model gut for starch.

  state that small molecules can pass through the wall of the small intestine

  explain that starch, protein and fat molecules are too large to be absorbed

  explain that specific vitamins and minerals are generally smaller and can be absorbed by the body

  produce a sequence of diagrams to illustrate that larger molecules are broken down to form smaller molecules in the gut

   Plants’ production of starch from glucose for storage is introduced in unit 9A ‘Inheritance and selection’. Minerals, eg calcium, and vitamins, eg vitamin C, are considered in more detail in unit 9B ‘Fit and healthy’.

   Interlocking bead models can be used to represent large and small molecules and to model the process of breakdown of molecules, such as starch into sugar molecules. Although such models do not accurately represent the structure of fats, they do help to get across the idea of complexity.

Safety

ensure pupils use their own saliva and that used test tubes are placed in disinfectant. Staff who clean apparatus should use gloves

   KS3 Biology What do digestive enzymes do?

   that food is digested by enzymes in the gut to form smaller molecules

   to represent a complex process using diagrams and text

   Through questioning, elicit pupils’ ideas about digestive enzymes as a means of breaking down larger molecules. Establish that the water outside the tubing in the model represents the blood system. Ask them to explain the process, eg using animations from CD-ROMs or video, or interlocking bead models of large molecules. Ask pupils to draw a sequence of diagrams and then write an explanation in their own words.

  state that food is digested by enzymes in the gut to form smaller molecules and that these pass into the blood

  describe the processes involved, eg by drawing diagrams, by using models, in writing

   Viewing animation of the process is very useful in helping pupils to internalise what is going on.

   Extension: pupils could produce a ‘flicker-book’ animation to represent the process.

   to identify factors relevant to a particular context

   to plan how to control variables

   to explain their results using knowledge of the human digestive system

   to show relationships between ideas by using links that show purpose and reservation

   Remind pupils of the range of food types with large molecules and explain that in addition to enzymes the conditions inside the gut assist the breakdown of large molecules, eg body temperature. Ask the pupils to discuss what other substances are found in the stomach. After the discussion inform the pupils that hydrochloric acid is produced by the lining of the stomach.

   Provide them with an opportunity to investigate the action of a particular enzyme, eg trypsin acting on the gelatine of exposed and developed black-and-white photographic film; protease acting on albumen.

   Ask pupils to suggest what might affect how well the enzyme digests the food, eg pH, temperature, and help them to plan an investigation, identifying what they are going to measure and which variables they will need to control. Ask pupils to produce an account of their investigation, relating what they found out to the conditions in the gut.

  suggest relevant variables, eg pH, temperature

  identify a way to keep variables, eg temperature, constant

  identify the conditions under which digestion occurs, eg at a temperature of 37ºC, and relate these to their results

   At  this stage, pupils do not need to know the names of specific digestive enzymes, although some pupils might find these out for themselves.

   In unit 7E ‘Acids and alkalis’ pupils may have found out about the use of acid in the human digestive system.

   The effect of pH changes on enzyme activity could be monitored using ICT.

   Extension: pupils could find out which is the best washing powder for an egg yolk stain, eg biological or non-biological. Be aware that some pupils may be allergic to biological washing powders.

Safety  

pupils’ plans must be checked for health and safety before practical work begins. Remind pupils how to safely heat test tubes of acid and other substances

    KS3 Biology Where are the products of digestion used?

   that the products of digestion are transported in the blood to other parts of the body

   that some food material cannot be digested and is egested

   Remind pupils about the way in which the body uses food, eg for energy, for growth, and ask them how the products of digestion reach other parts of the body. Use secondary sources, eg video clips, ICT simulations, to show how simple molecules, eg glucose molecules, are transported to cells, eg in the muscles.

   Ask pupils which of the food types they hadn’t considered during the work on the products of digestion. Establish that fibre and undigested food is passed through the gut and egested in faeces.

  state that the blood transports products of digestion to every cell in the body

  use models to describe how smaller molecules are transported in the blood

  state that some food material cannot be digested and is passed out of the body as faeces

   At key stage 2 pupils are likely to have learnt about blood being pumped around the body by the heart, but not about the role of the blood in transporting the products of digestion to other parts of the body. The body’s use of glucose in respiration is covered in unit 8B ‘Respiration’.

   Extension: pupils could be asked to find out why grass is not a source of food for humans.

    KS3 Biology Reviewing work

   to relate knowledge and understanding of food types to the processes of digestion

   Provide pupils with an appropriate selection of terms related to food and digestion and ask them to use these to make a concept map. Discuss pupils’ maps with them, asking them to identify areas of difficulty and challenging them to make and explain new connections.

  identify appropriate connections between ideas in this unit and explain their reasoning

   A concept map can show connections between different ideas in a particular topic. Pupils may have made concept maps in key stage 2.

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 Doc Brown's Revision  KS3 Science KS3 BIOLOGY Unit 8B Respiration

KS3 Biology About the unit

In this unit pupils learn:

  how cells are supplied with the materials they need for respiration

  how cells in animals and plants release energy

  that the process of respiration is similar in all cells

In scientific enquiry pupils:

  consider earlier ideas about circulation including how and why these ideas have changed and developed

  make observations and present these in a suitable format

  consider how to deal with factors that cannot be controlled when working with living materials

KS3 Biology Where the unit fits in

This unit builds on unit 8A ‘Food and digestion’, which needs to have been covered first. It is closely linked to the section on breathing and smoking in unit 9B ‘Fit and healthy’. The unit relates to work on foods and fuels in unit 7I ‘Energy resources’ and to work on oxygen and burning in unit 7F ‘Simple chemical reactions’.

The unit lays the foundation for work on the composition of the blood, the structure of blood cells and the circulatory system at key stage 4.

The energy transfer ideas of unit 7I ‘Energy resources’ are used in the context of respiration. Energy should be distinguished from ‘stuff’ (the food as energy resource or fuel).

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: describe an earlier model of circulation indicating how it does not match present-day evidence; explain why control experiments and sample size are important when investigating living organisms; make appropriate observations, recording them accurately and identifying patterns in data obtained

some pupils will not have made so much progress and will: recognise that ideas about circulation have changed; with help, identify variables relevant to a question; make observations and recognise patterns in data

some pupils will have progressed further and will: describe and explain some of the evidence leading to present-day ideas about how and why blood circulates

in terms of life processes and living things

most pupils will: describe the role of blood in transporting carbon dioxide from, and oxygen to, the lungs and explain why tissues need a good blood supply; describe aerobic respiration as a reaction with oxygen; describe some effects of an inadequate oxygen supply; describe and explain differences between inhaled and exhaled air and identify similarities in aerobic respiration in plants and animals

some pupils will not have made so much progress and will: recognise that oxygen is required for aerobic respiration and that oxygen and glucose are transported in the blood; describe differences between inhaled and exhaled air

some pupils will have progressed further and will: represent the process of aerobic respiration as a word and/or symbol equation and identify similarities with the burning of fuels; describe the features of alveoli and explain how damaged alveoli result in less gas exchange

KS3 Biology Prior learning

It is helpful if pupils know:

  that air contains carbon dioxide and oxygen, with other gases

  that smaller molecules, including glucose, are produced from larger ones in digestion

  that the heart pumps blood to circulate it through the body

  that cells are organised into tissues and tissues can form organs

  how breathing varies according to the body’s needs

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity. In this unit pupils:

  observe energy released in the combustion of sugar

  measure body temperature

  use a variety of materials, some of which are hazardous

  handle living animal material

Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  names of organs of the chest linked to breathing, eg lung, trachea, bronchus, ribcage

  names of cells and tissue substances linked to circulation, eg red blood cell, haemoglobin, artery, vein

  more specialised scientific vocabulary, eg carbon dioxide, oxygen, diffusion

  words with similar but distinct meanings, eg breathing, ventilation, inspire, respire, inhale, exhale

  words with different meanings in scientific and everyday contexts,
eg inspiration, aerobic, ventilation

Through the activities pupils could:

  discuss and respond to initial ideas and information, carry out the task and then review and refine ideas

  select relevant information and link to other information from a range of sources

KS3 Biology Resources

Resources include:

  a selection of living material, eg germinating peas, maggots, woodlice

  thermometers, liquid crystal strips

  reference sources, including ICT sources, providing information about how organisms, including aquatic ones, exchange gases with the environment

  information, eg labels, about the content of ‘high energy’ drinks/food supplements

  secondary sources of information about the heart

  software simulations and video clips illustrating the transport of substances in the blood

  video clips illustrating athletics or other sports

  information about intravenous feeding

  information concerning early ideas about circulation

KS3 Biology Out-of-school learning

Pupils could:

  find out what happens in the airways of asthma sufferers

  visit an aquarium and discuss with attendants how animals exchange gases in water

  find out about first-aid courses on artificial ventilation

    KS3 Biology How do cells use the food molecules absorbed after digestion?

   that products of digestion are transported in the blood to other parts of the body

   Ask pupils for their ideas about why the body needs food, reminding them of work done in unit 8A ‘Food and digestion’. Explain that this unit will concentrate on how cells release energy for growth, synthesis of new materials and body heat.

  identify that the body needs food for growth, synthesis of new materials, production of body heat

   This activity is designed to find out what pupils know about the products of digestion and how the body makes use of these. Teachers will need to bear this in mind in later work.

   that glucose is an energy resource for cells

   Ask pupils about ‘high energy’ drinks, who uses them and what they contain, and provide pupils with secondary sources of information. Establish that glucose is a major constituent of such drinks/foods and ask pupils to relate this to what they learnt about digestion of carbohydrates (starches) in unit 8A ‘Food and digestion’. Use secondary sources, eg video clips, software simulations, to show how small molecules, eg glucose, are transported in the blood to other parts of the body, eg muscles, brain.

  explain that glucose is transported in the blood to other parts of the body, including specific cells, eg  muscle cells, where glucose can become an energy resource

   Extension: pupils could be asked to find out about the composition of intravenous food used in hospitals and to explain why these components are used.

   that respiration is the sum of the chemical reactions which release energy from food molecules

   Remind pupils of work they did in earlier units on fuels and, by questioning, establish that when fuels burn they react with oxygen and release energy. Demonstrate this using 2.5cm of icing sugar in a tin-can ‘bomb’, igniting the fine powder with the flame of a candle and showing that this type of dust explosion can blow off the can lid. Emphasise that the chemical reaction in cells is much more controlled than the dramatic demonstration. Explain that, although burning does not occur, a similar reaction takes place between glucose and oxygen in the cells of the body and that this is aerobic respiration.

  recognise that oxygen is needed for aerobic respiration

  state that glucose is used for energy release

  identify differences between reactions in cells and burning, eg in the cell the release of energy is controlled

   Pupils will have explored burning fuels to release energy in unit 7I ‘Energy resources’. In unit 7F ‘Simple chemical reactions’ they will also have explored the production of carbon dioxide and water during the combustion of fuels containing carbon and hydrogen.

   The analogy with burning fuels is useful. However, pupils need to be aware that ‘fuels’ used by cells do not ‘burn’.

Safety

screens and eye protection should be used and pupils should be seated 2–3 metres away

    KS3 Biology How do cells use the food molecules absorbed after digestion? (Cont.)

   to use thermometers of different kinds

   that respiration can be represented by a word equation: glucose + oxygen R carbon dioxide + water, and this reaction releases energy

   to explain observations using scientific knowledge and understanding

   Present pupils with a range of observation activities, eg

    – observing a temperature difference between germinating peas and boiled peas

    yeast generating bubbles of carbon dioxide which are passed into lime water

    germinating peas and maggots in separate gauze cages over hydrogencarbonate indicator

    water weed shielded by black paper in hydrogencarbonate solution producing carbon dioxide

    measuring their own temperature

   Discuss their observations to establish that the hydrogencarbonate indicators show that the living material was producing carbon dioxide and the increased temperature measured by the thermometers shows that the living material was also releasing energy. Provide pupils with opportunities to discuss, in groups, what they observe and provide an explanation to the whole class.

   Explain that energy is released in cells by respiration, which is a process that uses nutrients from food and oxygen, and releases carbon dioxide, water and energy. Summarise the process of aerobic respiration in a word equation.

  record temperatures, reading scales accurately

  summarise respiration in a word equation: glucose + oxygen R carbon dioxide + water

  explain the increased temperature in terms of energy release during respiration

   Teachers will need to explain the use of the hydrogencarbonate indicator if pupils have not used it previously.

   Pupils’ attitudes to the appropriate care of living organisms need to be handled sensitively.

   Sensors and computer software can be used to monitor temperature and other changes in germinating peas.

   Pupils with visual impairment could use talking thermometers to record temperature.

   Extension: some pupils’ understanding of aerobic respiration could be reinforced using a ‘snap’ game with cards labelled ‘glucose’, ‘oxygen’, ‘carbon dioxide’, ‘water’ and a different coloured card for ‘energy’.

Safety

the safe approach (including everyday use) to taking body tempera­ture is to use liquid-crystal strips. If clini­cal thermometers are used, they need to be disinfected each time they are used

    KS3 Biology How does the oxygen needed for respiration reach the tissues of the body?

   that the exchanges of substances between cells and the blood occur adjacent to the capillaries

   that the blood transports substances to and from the cells of body tissues

   Ask pupils what they know about the heart and circulation of blood in humans. Provide pupils with a simple diagram of blood circulation or a card sort/sequence and labels activity. Ask pupils to describe the route glucose takes from the stomach to reach a leg muscle cell. Establish that oxygen enters the body through the lungs and ask pupils to describe the route oxygen takes from the lungs to a leg muscle cell.

  state that oxygen and glucose are carried in the bloodstream

  explain that oxygen (and glucose) pass from the bloodstream into nearby cells

  explain that carbon dioxide and water pass from cells into the bloodstream

   Pupils are likely to have learnt about the heart as a pump and blood circulating through blood vessels in the body at key stage 2. At key stage 3, emphasis is on blood as a transport medium. Details of the circulatory system are not required at this stage.

   It is not necessary for pupils to go into detail of how a red blood cell is adapted for carrying oxygen.

    KS3 Biology How does the oxygen needed for respiration reach the tissues of the body?

   why the heart needs to work efficiently

   to select relevant information and link to other information from a range of sources

   how a theory has been modified when predictions made from it are not supported by evidence

   Remind pupils of the heart’s structure and function using, eg illustrations, video clips, models, mammalian hearts, CD-ROMs. Discuss the heart’s pumping action as a double pump, one side supplying the lungs, the other side supplying the other body organs. Provide opportunities for pupils to discuss in groups and then annotate diagrams of the heart using arrows to show the direction of blood flow. Ask pupils to think about and predict the consequences of the heart not working efficiently in terms of blood supply to the tissues and lungs.

   Provide pupils with secondary sources so that they can find out about the development of ideas about the heart and circulation and scientific methods using, eg Galen, Vesalius, Harvey, Withering, Ibn-al-Nafis. Help them to draw out the ideas about experimenting and making inferences. Emphasise that scientific theories were based on persuasive argument and that there were long periods of time before ideas, even though not supported by evidence, changed.

  explain why the tissues, including the lungs, need a good blood supply

  synthesise information from a variety of sources

  recognise that theories change when they are not supported by evidence

   There is an opportunity to use IT simulations of heart action.

   Some teachers may wish to discuss holes in the heart leading to depleted oxygen supply to the tissues.

   Extension: pupils could be asked to find out about, eg

    – Galen: content of arteries and movement of blood

    – Vesalius: detailed anatomical observation and investigation contradicted earlier ideas

    – Harvey: argued only from evidence supported by experiment and observation that blood circulates constantly and the heart pumps blood

    – Withering: large number of observations before drawing conclusions, recognition that the popular idea of effect was wrong, first scientific investigation of a drug, eg digitalis

    Ibn-al-Nafis: discovered pulmonary circulation

    – Servetus, Columella, Da Vinci: could be added for studies of heart function. Circulation of the blood was known to the Chinese by the second century BC

    KS3 Biology What happens to the oxygen when it reaches the cells?

   that cells need a good supply of oxygen in order to release energy

   that carbon dioxide is produced during aerobic respiration

   Remind pupils of earlier work and review their understanding of the reaction in the cells between oxygen and glucose. Ask them to think about what happens if the blood cannot supply enough oxygen for the cell’s needs, eg during intense physical activity.

   Ask them about their own experiences and illustrate, eg with video clips of athletics. Ask pupils about the meaning of the word ‘aerobic’ and why aerobics in relation to exercise is so called.

   Extend to other situations where there may be a reduced oxygen supply, eg through illness, mountaineering. Reinforce the idea that carbon dioxide and water, as well as energy, are released from aerobic respiration and that carbon dioxide is removed from the cells in the bloodstream.

  state that oxygen is needed for cellular aerobic respiration

  describe some effects on the body of an inadequate oxygen supply

  state that carbon dioxide and water are products of respiration

   ‘Oxygen debt’ and the production of lactic acid in anaerobic respiration are dealt with in key stage 4. Some teachers may wish to introduce some pupils here to the idea of lactic acid formation.

 KS3 Biology Checking progress

   about the reaction in cells between glucose and oxygen

   how the blood transports glucose and oxygen around the body

   Provide pupils with a series of true/false statements or flashcards about respiration and the transport role of blood. Ask them to work in groups to classify the statements and to provide reasons for their choices. They should be shown how to discuss and respond to initial ideas and information, carry out the task, and then review and refine ideas. Use the work to form the basis of a summary of key points.

  identify the reactants and the products of respiration

  explain the role of the blood in supplying and removing substances to cells

  identify some effects of a reduced oxygen supply to respiring cells

  contribute to sustained group work to carry out and report on a task

   At this point teachers may wish to reinforce the idea that respiration and breathing have different scientific meanings.

    KS3 Biology What is the role of the lungs?

   that lungs are specialised organs where oxygen from the air enters the blood and carbon dioxide in the blood passes into the alveoli

   how the alveoli provide a large surface area for gas exchange

   Review, using quick questions, pupils’ understanding of the composition of air breathed into the lungs and the importance of oxygen for aerobic respiration. Ask pupils to suggest what happens to air when it enters the lungs. Establish, eg using simulation software, that oxygen enters the blood and is transported elsewhere, and that carbon dioxide produced in the cells passes out of the blood.

   Show illustrations, models or animated pictures of the fine structure of the lungs and ask pupils to suggest why the alveoli have so many blood vessels around them. Provide information about carbon dioxide and oxygen concentrations in the blood. Ask pupils to predict what happens in the alveolus. Help pupils to annotate diagrams with arrows to show the direction of movement of oxygen and carbon dioxide and describe gas exchange in terms of a supply of oxygen to the blood and removal of carbon dioxide from the blood.

   Show illustrations of damaged lungs from, eg emphysema, dust damage. Ask the pupils to describe the differences and predict what effects this damage may have on gas exchange.

  describe features of the alveoli, eg very thin walls, large surface area, the network of blood capillaries around the alveoli

  describe the movement of gases from air to blood and blood to air

  describe how carbon dioxide and oxygen are exchanged at the surface of an alveolus

  describe how damaged lungs will result in less gas exchange

   Pupils often focus on the body’s need for oxygen and should be reminded about the importance of the removal of carbon dioxide as a waste product. Air as a mixture with varying composition is covered in unit 8F ‘Compounds and mixtures’.

    KS3 Biology How are inhaled and exhaled air different?

   to make comparisons between the composition of inhaled and exhaled air

   to present findings in a suitable format

   to discuss and respond to initial ideas and information, carry out the task and then review and refine ideas

   Ask pupils to use what they know about respiration to predict the differences between inhaled and exhaled air.

   Show pupils how to demonstrate changes in oxygen concentration, eg length of time a candle burns in exhaled air compared to normal air, volume changes when oxygen is absorbed by alkaline pyrogallate. Ask pupils to investigate other changes in the air as they breathe in and out, eg presence of more carbon dioxide in expired air, pupils breathe onto cold mirrors or glass and test the moisture with cobalt chloride paper. Discuss the results with the pupils. Ask pupils to use reference sources to present their findings, including a table of changes in composition of air when it is breathed. Relate this to knowledge of respiration, deciding whether their predictions were correct.

   While the pupils are waiting for results, ask them to use reference sources to find out how aquatic animals and plants obtain oxygen from water.

  describe the differences in the concentrations of oxygen, water vapour and carbon dioxide in inhaled and exhaled air

  present their results in a table which relates their findings to other data about the composition of the air and their knowledge of respiration

   Pupils will have used the lime water test for carbon dioxide in unit 7E ‘Acids and alkalis’ and unit 7F ‘Simple chemical reactions’, and hydrogencarbonate indicator earlier in this unit.

Safety

pyrogallic acid (benzene 1,2,3 triol) can be dissolved in saturated sodium hydrogencarbonate to produce a less hazardous solution, with a lower pH than that commonly used. Pupils require eye protection during use. If pupils breathe into lime water, eye protection and sterilised mouthpieces are required

     Do other organisms respire in a similar manner?

   to turn ideas into a form that can be investigated

   to make decisions about how to deal with factors which cannot be controlled

   to use controls for comparisons

   how to work with living materials

   Ask pupils about the organisms they used earlier in the unit and ask them how they could find out if other living things also produce carbon dioxide during respiration. Provide suitable apparatus for holding living material, eg gauze platform in a boiling tube above a hydrogencarbonate indicator solution.

   Discuss the selection of living organisms, eg yeast, germinating lentils, small fruit woodlice, maggots, the use of a control apparatus without living material and relevant factors, eg mass of living material, temperature, activity, sensitivity of the indicator, length of time to leave it. Ask the pupils to write a plan for their investigation.

  identify factors that could affect the quantity of carbon dioxide produced

  recognise the need for a control

   Pupils should be encouraged to think of the welfare of small animals. It is more convenient to use invertebrates.

   Germinating lentils are convenient plants and work well.

Safety  

wash hands and wipe the bench with disinfectant after handling live material

   that plants and other animals produce carbon dioxide during respiration

   to make careful observations and draw conclusions explaining these in terms of scientific knowledge and understanding

   to use scientific terminology effectively and accurately in writing

   Help pupils to carry out the investigation they planned. Compare results from different investigations and ask the pupils to identify any trends, eg plant material produced less carbon dioxide than animal material, the more active animals produced more carbon dioxide.

   Draw together the results of the investigations and establish respiration as a process that takes place in the cells of plants and animals.

  recognise that other living things, including plant material, produce carbon dioxide during respiration

  integrate the results of others with their own to draw conclusions

  identify and describe patterns in the data

   Pupils should consider the welfare of small invertebrates.

   It may be necessary to leave the plant investigations set up for a longer period of time. Pupils will need to take this into consideration in any comparison of results.

   Photosynthesis is covered in unit 9C ‘Plants and photosynthesis’. Pupils often think that plants photosynthesise but do not respire. It is helpful to emphasise that plants do respire before photosynthesis is studied.

Safety  

wash hands and wipe the bench with disinfectant after handling live material

    KS3 Biology Reviewing work

   to summarise and make connections between key ideas in the unit

   Provide pupils with a diagram showing the gut, lungs, blood supply, heart and cells, and help them to produce a flow chart showing how expired carbon dioxide is derived from glucose, made available by digestion, and its reaction with inhaled oxygen.

   As appropriate, supply pupils with prepared phrases with which to label the flow chart and/or structured questions.

  connect ideas appropriately, eg in a flow chart, responses to questions

 

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 Doc Brown's Revision  KS3 Science KS3 BIOLOGY Unit 8C Microbes and disease

KS3 Biology About the unit

In this unit pupils:

  learn that micro-organisms share the characteristics of other living things

  find out about growing micro-organisms to make products, and about the role of micro-organisms in infectious diseases

  learn about the body’s defence systems and how immunisation can protect against microbial infections

In scientific enquiry pupils:

  consider how ideas about the transmission of infectious diseases have changed and are continuing to develop

  learn how scientists work together to investigate and reduce the transmission of infectious disease

  learn how to grow micro-organisms healthily and safely

  consider the number of measurements needed for reliable data

  identify and control relevant variables

  investigate the activity of yeast, evaluating proposed approaches

Some of this unit may be undertaken in relation to the school’s PSHE programme. Teachers will be aware of the need for sensitivity to pupils and their families who may have or have had, a particular illness or may have reduced resistance to infection.

KS3 Biology Where the unit fits in

This unit draws on ideas developed in the key stage 2 programme of study. It builds on unit 6B ‘Micro-organisms’ in the key stage 2 scheme of work and on unit 8B ‘Respiration’.

In unit 9B ‘Fit and healthy’, pupils have further opportunities to consider the transmission and incidence of infectious diseases.

There are opportunities to link with citizenship and PSHE in this unit in dealing with medical advances, the development of drugs and food safety.

This unit lays the foundation for work in key stage 4 on the body’s defences against infection and the uses of micro-organisms in biotechnology.

This unit also relates to unit 9E(i) ‘Ensuring quality production (food)’ in the design and technology scheme of work, and unit 20 ‘Twentieth-century medicine’ and unit 21 ‘Scientific discoveries’ in the history scheme of work.

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: describe how understanding of how some infectious diseases are transmitted has developed as knowledge about micro-organisms has increased; point out trends and patterns in first-hand and secondary data, draw conclusions from these and relate them to scientific knowledge and understanding

some pupils will not have made so much progress and will: describe how some infectious diseases are transmitted, point out some patterns in data and use these to draw conclusions

some pupils will have progressed further and will: describe how scientists’ interpretation of evidence has led to new ideas about the transmission of disease and to new drugs

in terms of life processes and living things

most pupils will: classify bacteria, fungi and viruses as micro-organisms, name some of the diseases they can cause and describe how they can be transmitted; describe some of the defences the body has against disease and describe immunisation as a way of improving immunity; recognise that antibiotics are effective against bacteria but not against viruses

some pupils will not have made so much progress and will: name some infectious diseases and describe how they can be transmitted; describe immunisation as a way of protecting against infectious disease

some pupils will have progressed further and will: explain how immunisation can improve immunity and describe how antibiotics may be effective across a wide spectrum or against specific bacteria

KS3 Biology Prior learning

It is helpful if pupils:

  know that micro-organisms are living organisms

  have explored the characteristics of micro-organisms and know that they feed, grow and reproduce like other organisms

  know that organisms respire aerobically and produce carbon dioxide during the process

  can name some diseases caused by micro-organisms

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity. In this unit pupils:

  plan and carry out an investigation of yeast

  grow lactobacilli and produce yoghurt

  observe the growth of bacteria and the effect of antiseptic and antibiotics

Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  words and phrases relating to micro-organisms and diseases, eg bacteria, viruses, fungi, measles, chickenpox, infection, pathogen, infectious disease

  words with precise meanings in scientific contexts, eg immunity, virus, food poisoning

  words with similar but distinct meanings, eg vaccination, inoculation and immunisation, antibiotic, anti-microbial

  words and phrases relating to scientific enquiry, eg sufficient data, epidemic, reliable data

Through the activities pupils could:

  listen for a specific purpose, note the main points and consider their relevance

  organise facts/ideas/information in an appropriate sequence

KS3 Biology Resources

Resources include:

  secondary sources, eg simulation software, CD-ROMs, illustrating the growth of micro-organisms

  datalogging equipment and software to monitor pH

  secondary sources to explore routine immunisation, ideas about side effects, immunisation in other countries

  information on routine immunisation programmes for young children

  resources to cultivate selected strains of micro-organisms

  autoclave or alternative equipment for preparation of materials and safe disposal of microbe-contaminated waste

  stock cultures of suitable micro-organisms

  secondary sources, eg photographs, advertisements, medicine packaging, relating to the nature and uses of micro-organisms

  case studies of tracking and dealing with an outbreak of an infectious disease, eg Ebola, cholera, E. coli

  data about the incidence of bacterial disease over the last 60 years

  secondary data showing the incidence over the last century of a major childhood disease for which there is now immunisation

KS3 Biology Out-of-school learning

Pupils could:

  read leaflets on immunisation available in doctors’ surgeries

  follow news stories about outbreaks of diseases such as typhoid, dysentery or cholera after natural disasters

  visit a dairy, creamery, cheese factory, brewery

  read fiction based on epidemics, eg Siege of Krishnapur, Story of San Michele

  find out about changes in life expectancy after childbirth since 1900

 KS3 Biology What are micro-organisms and how do we grow them?

   that there are different types of micro-organism

   that many micro-organisms are useful, eg fungi are a source of antibiotics and are used in making food products

   Use oral questions to establish what pupils know about micro-organisms.

   Provide pupils with stimulus material to explore the range of micro-organisms and their uses or occurrence, eg bread, yoghurt, wine as useful products of micro-organisms, mushrooms and other fungi, large-scale photomicrographs of bacteria and viruses, advertisements for materials which kill household germs, an empty antibiotic bottle. Provide them with additional secondary sources, eg video clips, simulation software providing further information about micro-organisms. Discuss pupils’ observations with them and help them construct a table comparing the three kinds of micro-organism.

  identify three types of micro-organism, eg bacteria, viruses, fungi

  describe the features of each of these three types of micro-organism in terms of, eg relative size, shape, structure

   Pupils learn in key stage 2 that there are micro-organisms that cause rotting and disease, and that micro-organisms are used to make foods. However, they may not have used terms such as, ‘bacteria’, ‘virus’ or ‘fungi’.

Safety

– pupils should not be allowed to eat food samples. All cultures should be sealed. Mouldy food should be sealed in plastic bags, containers or Petri dishes to ensure spores are not released

   KS3 Biology  What are micro-organisms and how do we grow them? (Cont.)

   to share ideas and information, carry out the task and then review ideas

   to decide what to measure

   how to control variables

   about the number of measurements needed for data in which they have confidence

   that yeast respires like other organisms

   to collaborate with other investigative groups to gather reliable data and draw valid conclusions

   Ask pupils what they know about yeast from advertisements they may have seen, eg yeast respiration causing bread dough to rise. Discuss with them how they could investigate how increasing the quantity of sugar affects the quantity of carbon dioxide released, eg by placing a yeast/flour/glucose dough in a measuring cylinder in a warm environment, or by collecting bubbles from a yeast/glucose suspension.

   Help pupils to plan an investigation so that together they obtain sufficient valid and reliable data.

  evaluate methods proposed and agree on a common approach

  identify variables they need to control

  work out how many measurements will be obtained and indicate whether they will have confidence in their results

  explain that carbon dioxide is produced during aerobic respiration

  collect and store reliable and valid data using the same methodology

  identify a trend in the data,
eg the more sugar is added, the greater the volume

  relate results to scientific knowledge and understanding, eg increase in volume is due to carbon dioxide produced in respiration

   Pupils may have made bread with or without yeast in key stage 2, and tried keeping yeast and sugar in a warm and in a cold place and testing the gas produced.

   The effect of sugar on yeast activity can be observed in a limited period if the yeast is fully active before starting, and the solutions are pre-warmed and quantities of materials, eg flour, glucose, are dispensed in advance. Groups of pupils will need to collaborate to obtain a sufficiently wide range of values, including repeat measurements, to draw conclusions.

   This relates to work on respiration in unit 8B ‘Respiration’.

Safety

school-based training in aseptic techniques for staff may be necessary. All work with micro-organisms should be carried out only after appropriate risk assessments have been consulted

– pupils’ plans must be checked for health and safety before practical work begins. Ensure that plans do not involve a totally sealed system

    KS3 Biology What are micro-organisms and how do we grow them? (Cont.)

   that bacteria can be grown

   that manufacturing processes use micro-organisms to make products

   to recognise hazards when working with living materials and to take action to avoid them

   Establish through questioning the outcomes of the yeast investigation, emphasising that carbon dioxide is produced as yeast respires aerobically and grows. Discuss with pupils ways of growing bacteria, using video clips and illustrations to demonstrate growing bacteria on agar plates, eg in a hospital laboratory.

   Demonstrate how to inoculate a nutrient agar plate, using appropriate aseptic techniques when handling micro-organisms, and help pupils to do this themselves.

   Provide pupils with reference material to find out about growing bacteria or fungi to make a product, eg yoghurt, cheese, Quorn (mycoprotein).

  use a procedure to grow micro-organisms

  describe a process which involves growing micro-organisms to make a product

  recognise hazards when working with living materials and produce information about working safely

   It takes about 24 hours to grow lactobacilli and make a pot of yoghurt, but yoghurt can be cultured in test tubes over a few hours, and changes monitored. Milk thickening, due to protein breakdown and coagulation, can be measured by timing the passage of a fixed volume through a pipette or tap funnel using refrigerated samples.

   A visit to a microbiology laboratory, bakery or creamery or a visit from a microbiologist or food scientist would enhance this unit.

   Alternative: pupils could make yoghurt using, eg different types of milk, and monitor its progress, eg by recording change in pH (using datalogging equipment) or changes in viscosity.

Safety  

yoghurt made for consump­tion should not be made in a science lab but in a food technology area

    KS3 Biology Can micro-organisms be harmful?

   that some micro-organisms can cause disease

   that micro-organisms enter the body by a range of mechanisms

   Ask pupils how colds pass from person to person in a class. Use their answers to explain the term ‘infectious’ and introduce them to viruses as a form of pathogen.

   Discuss other infectious diseases and how they are transmitted. Provide pupils with reference sources with which to construct a table of methods of transmission, with examples of diseases and causative agents.

   Help pupils to generate a list of ways to avoid infections and then use their ideas to write a leaflet for travellers to a long-haul destination on how to avoid infection by local diseases, eg water-borne intestinal infections, malaria.

  recognise that micro-organisms can cause infections, eg food poisoning, TB, colds, tetanus, malaria, meningitis, athlete’s foot

  describe a range of mechanisms by which micro-organisms enter the body,
eg food- and water-borne, droplet/air-borne, vectors, blood-borne passage across the placenta and via breastfeeding

  produce a leaflet giving advice on avoiding infection

   Pupils may have had experiences of having immunisations for trips abroad, which can be drawn on. This should be handled sensitively for pupils whose parents do not agree with immunising children.

   Pupils may raise the issue of AIDS during this work. The school sex education, PSHE policy and guidance should be consulted.

   Extension: pupils could be asked to find out more about some current public health issues, eg the increase in tuberculosis, the increased demand for clean water in a UK city, ‘blue flag beaches’ and the factors affecting the safety of seawater.

   how a theory can be used to predict behaviour which can be tested by collecting evidence

   to listen for a specific purpose, note the main points and consider their relevance

   how scientists today tackle the spread of infectious disease

   Ask pupils to find out about an example of people preventing the spread of disease when the role of micro-organisms was not known, eg the residents of Eyam in Derbyshire restricting the spread of plague, the work of Dr John Snow identifying wells as the source of cholera infections, the work of Finlay on yellow fever.

   Invite groups of pupils to explain what was done and ask others to evaluate how effective approaches would have been in the light of knowledge about micro-organisms.

   Establish differences between some of the stories, eg John Snow’s actions were based on evidence about the distribution of cases of cholera, while the actions of others were not based on observed data. Provide pupils with information about a modern outbreak of a disease, eg Ebola, cholera,
E. coli,
and ask pupils to identify the range of people involved in containing the spread of infection. Help them to present findings, eg as a poster, flow chart.

  present information about a method of avoiding infection

  relate the methods to knowledge about micro-organisms and evaluate their effects

  describe the contributions of different scientists in dealing with an outbreak of disease

   Extension: pupils could be asked to find out about the work of Finlay on yellow fever and how his theories were only accepted once it was known that mosquitoes are carriers of malaria.

    KS3 Biology Checking progress

   to recall key points, terms and concepts

   Provide pupils with a range of short questions, testing recall of the main types of micro-organism and their uses, the diseases they cause and how infections are transmitted from person to person. Extend for some pupils by asking questions about the ways in which understanding of infectious diseases has depended on our understanding of micro-organisms.

  show by their responses that the main points have been recalled

   Teachers may wish to point out that our understanding of the transmission of infectious diseases is by no means complete, eg the transmission of BSE.

    KS3 Biology How can we protect ourselves against infectious diseases?

   that the body has natural barriers to infection

   that the production of antibodies and specialised cells in the blood are part of the defence systems of the body

   to listen for a specific purpose, note the main points and consider their relevance

   Explore pupils’ ideas of why people are seldom ill despite surroundings rich in potentially harmful micro-organisms by asking them to complete a concept map using a variety of terms, eg bacteria, virus, hygiene, immunity, vaccination, skin.

   Use pupils’ ideas to explain natural barriers to infection, and help pupils to annotate a diagram of the body with natural defence mechanisms. Ask pupils why young children are sometimes less resistant to infections than older children and why breastfeeding can help.

   Use video clips, ICT, slides or illustrations to show the action of white blood cells engulfing micro-organisms. Remind pupils about listening for a specific purpose and thinking about the relevance of the points made. Explain that other white blood cells make matching antibodies that identify and hinder specific microbial activity. Use the presence of antibodies in, eg blood, to link with the previous activity. Point out that all kinds of micro-organisms can cause disease and that each type of micro-organism needs a different set of antibody-making cells. Ask pupils to write a short passage about how blood cells defend against disease.

  identify natural barriers against infection, eg dry skin, lysozyme, etc in tears and sweat

  recognise that each type of micro-organism provokes a different set of antibodies

  describe how white blood cells defend the body against disease, eg engulfing micro-organisms, making antibodies

  describe antibody action,
eg marking infecting micro-organisms, entangling micro-organisms

  explain how blood cells defend against disease

   It is not necessary for pupils to learn terms such as ‘lymphocyte’ or ‘phagocyte cell’ at this stage. Further work on blood is included in key
stage 4.

   Pupils sometimes find it hard to distinguish between infectious illnesses and other forms of illness, eg dietary.

   Teachers will be aware of the need for sensitivity to the circumstances of pupils and their families who may have reduced resistance to infection.

    KS3 Biology How can we protect ourselves against infectious diseases? (Cont.)

   that not all diseases caused by micro-organisms can easily be treated by drugs

   that some medicines contain antibiotics which kill bacteria or prevent their growth

   that scientific advances may depend on creative thought and interpretation of evidence

   Using stimulus material such as video clips, discuss with pupils how infections are treated. Identify prevention of transmission and the action of drugs to kill or suppress micro-organisms, or to relieve symptoms.

   Remind pupils of how to work safely with micro-organisms and help them to investigate the effect of common household anti-microbial compounds,
eg toothpaste, anti-perspirant, antiseptics, disinfectants, sterilising solutions, on the growth of bacteria on a nutrient agar plate. Establish that these are not antibiotics but contain agents that can kill bacteria.

   Ask pupils about medicines they cannot buy from the chemist but have to obtain on prescription, and ask them why this is so. Use their answers to explain that antibiotics kill particular bacteria and are not effective against all types of bacteria, eg neomycin sulphate against the bacteria causing middle-ear infection.

   Challenge pupils to explain why:

    people are not prescribed antibiotics when they have a cold or chickenpox

    some bacteria are resistant to antibiotics

    people are always told to complete the course of an antibiotic

    many doctors wish to limit the prescription of antibiotics

   Ask pupils to find out about the initial observation of antibiotic activity by Fleming and the further development by Florey and Chain. Provide them with data about the incidence of diseases that are treatable by antibiotics over the last century and help them to explain trends and patterns.

  show that they can work with micro-organisms safely

  describe the effect of household anti-microbial substances on bacterial growth

  state that antibiotics are effective against bacteria but ineffective against viral infections

  show in their writing that scientific advance may come from creative thought and interpretation of evidence

   Bacteria grown on a slope of nutrient agar containing disinfectant can be used to show the effects of increasing concentration of antiseptic – refer to National Council for Biotechnology Education (NCBE) publications or the Microbiology In Schools Advisory Committee (MISAC).

   Extension: pupils could observe the effect of antibiotics directly by adding discs of penicillin or streptomycin to agar plates spread with a variety of bacteria, which will show different sensitivities to the antibiotic used.

   Extension: pupils could also be asked to find out about antiviral drugs that are being developed.

Safety  

school-based training in aseptic techniques may be necessary. Employer’s risk assessments relating to work with culture plates should be fol­lowed

    KS3 Biology How can we protect ourselves against infectious diseases? (Cont.)

   that immunisation helps to protect against some diseases

   that antibodies can pass through the placenta to the foetus and through breast milk to a baby

   that vaccines contain material which stimulates body defences

   Ask pupils about which immunisations they have had, eg polio, DPT (diphtheria/whooping cough/tetanus), MMR (measles/mumps/rubella), HIB (Haemophilus influenzae B), Heaf tests and TB (tuberculosis), and why they had them.

   Explain what is in a vaccine. Show, by using charts, video clips and simulation software, what happens to antibody levels in the blood as the programme of immunisation proceeds. Challenge pupils to predict what happens in the blood when someone re-encounters the micro-organisms against which they have been immunised. Ask pupils to annotate a graph of antibody changes in the blood after, eg DPT, immunisations. Explain that antibodies pass to babies via breast milk and play an important role in protecting newborn babies from disease.

  explain ‘immune’ as meaning resistant to disease and that immunisation is a way of raising immunity

  recall that vaccines contain microbial material, eg weakened strains, dead micro-organisms, extracts of micro-organisms, that cannot cause infections

  explain that antibodies pass to a baby across the placenta and via breast milk

  explain that immunisation protects the body against some diseases because antibodies are made more quickly in response to infection

   It is useful to have a box of information snippets for research, eg measles immunisation required for entry to US schools, World Health Organization programmes, newspaper clippings about vaccine scares, comparative data on the incidence of measles and ensuing complications in developed and developing countries.

   to identify patterns in data from secondary sources and to try to explain them

   to organise facts/ideas/ information in an appropriate sequence

   Provide pupils with secondary data on the incidence of a major childhood disease, eg diphtheria from 1910 to 1955 in a city location. Ask them to relate patterns to the introduction of immunisation and the start of a free health service.

   Ask pupils to find out about programmes of routine immunisations using reference materials, ICT and the internet. Use the information to write a magazine article about the advantages and disadvantages of routine immunisations.

  describe how the incidence of, eg diphtheria, varied over the period and relate changes to social changes, eg the introduction of immunisation

  present a point of view in writing, using statistical evidence and linking points persuasively

   Statistics on disease incidence are available in government reports such as those of the chief medical officer, available from HMSO bookshops.

   Some teachers may want to go further and discuss why some immunisations need boosters every few years, eg against tetanus, while others, eg against cholera, are not very effective.  The relationship between the incidence of infectious disease and other factors, eg diet, is explored further in unit 9B ‘Fit and healthy’.

     KS3 Biology Reviewing work

   to collate ideas about micro-organisms, diseases and defences against disease

   to identify key points about micro-organisms and their relationship to disease

   Ask pupils to produce a concept map of micro-organisms and diseases using the terms in this unit. Using their concept maps they can generate a list of questions to ask each other about micro-organisms.

   Ask pupils to go through the work they have done in this unit and pick out five or six key points, and then in groups agree ten amongst themselves. Compare the lists of different groups and agree a summary of key points with the class, in which closely related points are grouped together.

  demonstrate, by their responses, understanding and recall of key points

  identify, summarise and group key points

 

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 Doc Brown's Revision  KS3 Science KS3 BIOLOGY Unit 8D Ecological relationships

KS3 Biology About the unit

In this unit pupils:

  study a habitat in detail and learn how:

    – organisms can be identified and sizes of populations compared

    – feeding relationships can be modelled quantitatively

    – living things within a community influence each other and are affected by the environment

In scientific enquiry pupils:

  model consequences of environmental changes within a habitat

  learn how to sample in biological investigations

  collect, present and interpret data and use this to make predictions

  undertake fieldwork to collect information about organisms within a habitat

The activities in this unit are intended to be combined into a full day of fieldwork. This could focus on habitats studied in unit 7C ‘Environment and feeding relationships’, but it would be preferable to use a contrasting habitat. Many urban environments provide ample opportunities for the work in this unit. Alternative classroom-based activities are suggested within the unit.

KS3 Biology Where the unit fits in

This unit builds on unit 7C ‘Environment and feeding relationships’ and unit 7D ‘Variation and classification’.

It draws on unit 8C ‘Microbes and disease’ and relates to unit 9C ‘Plants and photosynthesis’ and unit 9G ‘Environmental chemistry’. It provides a foundation for unit 9D ‘Plants for food’.

It also provides a foundation for work in key stage 4 on energy transfer through an ecosystem and its relationship to food production.

This unit provides links with unit 3 ‘Processing text and images’ and unit 7 ‘Measuring physical data’ in the ICT scheme of work, with opportunities for presentations on, and measurements in, the environment.

Unit 7 ‘Rivers – a fieldwork approach’ in the geography scheme of work also covers fieldwork

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: suggest what data should be collected to investigate a habitat and choose appropriate apparatus and techniques to make measurements and observations; use a sampling technique to collect data to compare populations in habitats; use ICT to collect, store and present information in a variety of ways

some pupils will not have made so much progress and will: collect data to investigate a question about a habitat using appropriate apparatus and techniques; use ICT to collect, store and present information

some pupils will have progressed further and will: plan how to collect reliable data, taking into account the fact that variables cannot readily be controlled

in terms of life processes and living things

most pupils will: classify some plant specimens into the main taxonomic groups of plants; identify and name organisms found in a particular habitat and describe how they are adapted to the environmental conditions, explaining how the adaptations help survival; relate the abundance and distribution of organisms to the resources available within a habitat and begin to represent this using pyramids of numbers

some pupils will not have made so much progress and will: name some organisms found in a habitat and describe how they are adapted to environmental conditions; recognise that the abundance and distribution of organisms is different in different habitats

some pupils will have progressed further and will: explain how pyramids of numbers represent feeding relationships in a habitat

KS3 Biology Prior learning

It is helpful if pupils:

  know that different living things live in different habitats

  can describe ways in which animals and plants are adapted to survive in a habitat

  can represent feeding relationships by food chains and food webs

  know that organisms can be classified into animals and plants and about the main taxonomic groups of animals

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity. In this unit pupils:

  carry out fieldwork outside the school

  handle a variety of living things

Many employers have specific guidance on fieldwork. Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  words and phrases relating to the environment, eg community, habitat, pyramid of numbers

  words with similar but distinct meanings, eg predator, carnivore, habitat, environment, ecosystem

  words and phrases relating to the classification of plants, eg taxonomic group, mosses, ferns, conifers

  words and phrases relating to an investigation of a habitat, eg environmental conditions, quadrat sampling, transect, population sizes, reliable data

Through the activities pupils could:

  describe and evaluate how the work was undertaken and what led to the conclusions

  group sentences into paragraphs that are clearly focused and well developed

KS3 Biology Resources

Resources include:

  secondary sources to explore animal and plant communities living in different habitats,
eg reference books, CD-ROM, access to internet

  specimens of a variety of plants, eg mosses, liverworts, ferns, conifer branches, pelargonium, grasses in flower

  secondary data providing information on food webs, population sizes, etc, in a range of environments

  keys and field guides for use in fieldwork

  datalogging equipment and software

  prepared spreadsheet template for recording data from fieldwork

  apparatus for collecting specimens during fieldwork

  quadrats and other sampling apparatus

  video camera and/or digital camera and associated software

  simulation software for investigating predator-prey interactions

KS3 Biology Out-of-school learning

Pupils could:

  visit a range of habitats, eg nature reserves, bird sanctuaries, national parks

  visit libraries or museums to find out more about the animal and plant communities living in different habitats, and their adaptations, and about issues related to the environment

  watch wildlife videos and television programmes about a range of very different habitats

  take part in environmental awareness or improvement projects

  use internet sites, eg www.ase.org.uk/envlnk.html that offer opportunities to find out about ecological relationships, biodiversity and environmental issues

  read newspaper articles, magazine articles and books about habitats, including those that are under threat or where protection schemes have resulted in species re-establishing themselves

  read fiction with an emphasis on the natural environment, eg Watership Down

    KS3 Biology How can animals be classified?

   that organisms only survive in a habitat where they have all the essentials for life and reproduction

   Review what pupils recall from previous work on living things in the environment by providing stimulus pictures of different habitats and asking pupils to suggest what types of animal and plant live there. Ask pupils to suggest reasons why the animals and plants differ, focusing on environmental factors. Use the opportunity to encourage pupils to think about how organisms get all the things they need to survive in these habitats.

  suggest how organisms living in different habitats obtain the essentials for life and reproduction

  identify organisms likely to be found in a habitat

   The first two activities are intended to find out what pupils know and understand about living things in habitats. Teachers will need to bear this in mind in later work.

   that animals can be divided into vertebrates and invertebrates and that these groups can be further subdivided

   Remind pupils of the work they did in year 7 on classification and using,
eg photographs, ICT resources, as stimulus material, establish that it is helpful to classify organisms into plants and animals and that animals can be subdivided into vertebrates and invertebrates.

  describe differences between vertebrates and invertebrates

  name some groups of invertebrate and give examples of these

   The number of vertebrate and invertebrate groups introduced is likely to depend on the habitats to be investigated in the next part of the unit. At this stage it is not necessary for pupils to distinguish between levels of subgroup, eg phylum, class.

   In unit 7D ‘Variation and classification’ pupils consider the classification of animals.

    KS3 Biology How can green plants be classified?

   that green plants can be subdivided into those with vascular tissues (xylem and phloem) and complex leaves with a waterproof cuticle, and those without

   Show a selection of common living plants, eg mosses, liverworts, ferns, conifer branches, pelargonium and grass in flower. Ask pupils to suggest where, and in what environmental conditions, each might be found. Show how plants are subdivided into two groups: plants without waterproofing layers, eg mosses, which are confined to damp environments, and plants with waterproof cuticles, which inhabit a wider range of habitats.

   Ask the pupils about other features shown by the plants. Use their suggestions to form the basis of classification, eg ferns, cone-producing plants and flowering plants.

  recognise that plants are subdivided into groups based on characteristics such as vascular tissue and seed- or spore-bearing reproduction

  explain why mosses are found in places that are damp

   The purpose of the classification work is to help pupils to make sense of what they find during the major fieldwork activity in this unit.

   For many pupils, teachers will wish to simplify the terms used to describe plant characteristics.

   Some pupils may wish to explore the subdivision of flowering plants into monocotyledonous and dicotyledonous plants. Conifers are contained within gymnosperms, but not all gymnosperms bear cones.

   Extension: pupils could classify a range of living, preserved and photographic plant material using the main taxonomic features.

    KS3 Biology How do plants, animals and environmental conditions interact in a habitat?
     a) How can we collect data to answer questions about a habitat?

   how to frame questions that can be investigated

   to use scientific knowledge and understanding to raise questions about habitats

   to decide what data might be collected and how to present data

   how to use ICT to measure and record environmental factors

   Organise fieldwork in a suitable location, eg woodland, pond, stream, school grounds, wall, paving stones, park, sand dunes, rocky shore, and discuss with pupils the questions they will try to answer during the work, eg

    – What lives there?

    – Why do communities differ in different habitats?

    – How can we measure sizes of populations of living things?

   Ask pupils for ideas about data they will need to collect to answer the questions, how they will go about it and what they will do with the data collected when they return to school.

   Remind pupils of how to use dataloggers to collect remote data when outside, eg temperature variations, dissolved oxygen, light intensity and humidity, and how to produce graphs from the data collected. Discuss the formats to be used for presenting results in the fieldwork activity.

  decide on questions to be investigated

  suggest data to be collected

   It is helpful if the locality chosen allows two contrasting habitats to be studied.

   Pupils are likely to have used environmental sensors and computers to collect and display environmental data in unit 7C ‘Environment and feeding relationships’.

Safety  

– all off-site visits must be car­ried out in accordance with employer’s guidelines. Pupils’ plans must be checked for health and safety before practical work begins

   about the importance of sampling in biological studies

   about the use of quadrats as a sampling technique for investigating populations

   to sample using quadrats

   Ask pupils to suggest how they might go about finding out the size of a population of a plant or animal living in a habitat. Help them to realise the limitations of simply counting in some situations, eg where the animals are difficult to find, or where they occur in large numbers. Explain the principles behind sampling as a means of collecting this type of data in biological studies. Describe different methods of sampling populations including the use of quadrats.

   Provide groups with trays of sand, in which small steel tacks have been buried. Show them how to use small wire square quadrats to sample areas of the tray, using a magnet to remove the tacks within a quadrat. Ask them to estimate how many tacks are hidden, by taking ten quadrat samples, and to explain why taking ten samples gives more reliable data than taking one.

  explain why it is sometimes necessary to use sampling methods to get information in biological studies

  use data from quadrat sampling to give information about population size

  explain why one sample might provide misleading results

   Detailed mathematical treatments are not required in this key stage.

   This activity illustrates how a sample can be taken. It is not a substitute for sampling within a natural habitat.

    KS3 Biology b) What lives there?

   to observe and record the organisms which comprise the living community in a habitat

   to work safely with living things

   to show sensitivity to living things in their environment 

   Agree with pupils what data they are going to collect and show them ways of finding and observing living things in the habitat being studied. Make sure they understand issues relating to safe working and care for living organisms.

   Show pupils ways of collecting specimens of animals, eg using pooters.

   Provide pupils with resources, including keys, field guides to help them find, collect, and identify typical animals and plants that they may come across. If possible, help pupils to use a digital camera to make a record of the habitat and organisms found.

  observe and record the organisms which comprise the living community in a habitat

  work safely with living things and show sensitivity to them

  make records in an appropriate way, eg using a digital camera

   A prepared spreadsheet template on a portable computer can help with the collection of data in the field.

   If small invertebrates are removed from their habitat, ensure they are treated with care and returned as soon as possible.  Avoid disturbing the habitat. Plants should not be removed unnecessarily. Stones or logs should be replaced if they are turned over.

   Pupils could be reminded that most micro-organisms within a habitat will not be found in this kind of activity.

Safety  

wash hands after handling animals. Pooter mouthpieces should be disinfected each time they are used. Wipe benches with disinfectant

   that different habitats support different living things

   to describe and evaluate how the work was undertaken and what led to the conclusions

   If possible, ask different groups of pupils to make and collect data about the communities in two different habitats within the same locality, and share findings as a report in the classroom.

   Ask pupils to produce a report of their findings, describing what they did, comparing the communities and saying what led to their conclusions.

  describe how the communities in two habitats differ

  describe, eg in an OHT/ Powerpoint presentation, how they carried out their work and explain how they came to their conclusions

   Information on a second habitat could be provided from secondary sources and studied in the classroom.

   As a classroom-based alternative, ask pupils to search sources of secondary data about the animals and plants found in two different habitats, eg pond and stream; two soil communities; different stages of sand dune; woodland shrub layer and leaf litter; rocky and sandy shores.

    KS3 Biology c) Why do the communities differ in different habitats?

   to use ICT to measure, record and describe environmental factors

   that different habitats have different environmental features

   Agree with pupils what data they are going to collect about the environmental factors of the habitat, eg temperature variations, light intensity, dissolved oxygen. Provide them with the appropriate apparatus, including dataloggers. Ask pupils to make a record of environmental conditions.

  collect data, eg temperature variation, light intensity within a habitat, using ICT

  use data collected to compare different habitats

   It may be helpful to decide beforehand on the format for recording environmental conditions. If a spreadsheet is used, pupils could investigate the data and produce graphs.

   Many CD-ROMs and internet sites are good sources of information on environmental conditions and on the organisms associated with different habitats.

   to group sentences into paragraphs that are clearly focused and well developed

   Ask pupils to write a report, including graphs of the data, about ways in which the two environments are different and encourage them to make associations between some of these conditions, eg in ponds, warm conditions and abundant plant growth can result in low oxygen levels, fast-flowing water in streams leads to cooler conditions.

  produce a report comparing two environments, incorporating appropriate data and other information

   The term ‘habitat’ refers to a place; ‘environment’ refers to the surroundings. In this activity, pupils are comparing the environmental features of two habitats and are therefore comparing two environments. Pupil records of comparisons of environments could be combined into one piece of work.

   that organisms show adaptations to environmental conditions

   that both plants and animals are adapted to ensure the survival of the species

   Ask pupils to make suggestions about how the conditions in each habitat influence the communities of organisms living there, eg by asking why there is more of this here than over there, and ways in which animals and plants are adapted for the problems of living within those environmental conditions, eg pond communities contain rooted plants on the fringe and floating plants in the middle of the pond, and an abundance of free-swimming animals, while fast-running streams may have plants with long, flexible stems, and animals adapted to holding on to a stony substrate.

   Help pupils to present their work as a wall display, including images of animals and plants showing relevant adaptations.

  describe organisms which show adaptations for particular habitats, and explain how these help the organisms to survive

  explain that both plants and animals are adapted to ensure the survival of the species

   As a classroom-based alternative, ask pupils to search secondary sources of information, or use real data about the environmental conditions of the two habitats being compared, eg

    temperature at different depths, flow rate, light intensity, availability of dissolved oxygen for two aquatic habitats

    temperature, moisture, organic content, mineral content, pH for two soils

    air temperature, humidity, light intensity, wind, for two terrestrial habitats

    KS3 Biology d) How big are the populations in the habitat?

   how to use quadrat sampling techniques to collect information about populations of organisms

   how to record data in appropriate ways

   Remind pupils about quadrat sampling and help them to collect quantitative data about number and distribution of organisms, eg count and find out about distribution of weeds on a school field, limpets on a rocky shore or earthworms in the soil; estimate percentage cover of different plant types in different habitats or in different areas of a habitat, such as along a transect. Arrange for pupils to collect comparative information from two habitats, or different parts of a habitat for which environmental data has also been collected.

  collect information about the number and distribution of organisms in a quadrat sample

  use sample data to estimate a population

  record data in appropriate ways

 

   that abundance of organisms in habitats is affected by environmental factors such as availability of light, water and nutrients

   that distribution of organisms in an environment is affected by environmental factors

   that the size of a population depends on resources

   Ask pupils to represent the data graphically, to make comparisons of the data and to suggest reasons for the distribution of organisms. Encourage them to consider the range of resources needed by animals, eg nesting sites, mates, and how environmental differences affect numbers and distribution of organisms. They should also be able to suggest ways in which organisms may influence each other, eg a large tree shading the area below it, preventing other plants from growing; availability of food influencing animal distribution.

   Help pupils to bring together all the work resulting from their field trip as a classroom display.

  suggest how environmental factors, eg availability of light, water and nutrients, affect numbers of organisms

  describe how the distribution of organisms depends on environmental factors

  explain how the size of a population depends on resources

   Data collected in the field may need to be supplemented by data from secondary sources.

   If possible, compare results with those from a previous year. Building up long-term data can help to make sense of some of the variables noted.

    KS3 Biology How do living things in a community depend on each other?

   that all feeding relationships within a habitat are interconnected

   that food webs are made up of a number of food chains

   to make predictions about the effect of different environmental factors on plant and animal populations

   to use ICT to model population changes

   that plants benefit from waste products and the decay of other organisms

   Review pupils’ understanding about feeding relationships by providing them with examples of food webs to analyse. Ensure that they can identify the food chains within a food web, and that they understand the terms ‘producer’ and ‘consumer’ and the flow of materials through the food chain.

   Challenge pupils to predict the effects of making changes to the numbers of one type of organism. Encourage pupils to go beyond simple relationships by considering knock-on effects of a single change, eg as the number of rabbits decreases, more grass will grow, providing more food for other grass-eating animals, whose numbers may increase as a result.

   Ask pupils to consider a range of examples of such changes in communities and their consequences. Extend the work by asking pupils to use a computer program to model changes, eg the effect of changing initial population sizes of predators and prey. Ask pupils to look for patterns in graphs produced from the data, to use these to make predictions about what will happen next and to test their predictions by allowing the simulation to run on.

   Challenge pupils to explain how plants benefit from the other organisms in the community.

  identify the food chains which make up a food web

  use the terms ‘producer’, ‘consumer’ and other terms related to feeding

  describe how a food web shows the feeding relationships within an environment

  predict how changing the size of one population will affect the numbers of other species

  present data from simulations as graphs and make predictions from patterns in these

  describe ways in which plants depend on other organisms

   Pupils will have constructed food webs in unit 7C ‘Environment and feeding relationships’.

   Data from the fieldwork could be drawn on for the rest of this unit. It will need to be supplemented by secondary data.

   A visit from an ecologist or environmental scientist to tell pupils about how he/she gathers evidence would enhance this unit. Pupils could be asked to use their own experience to prepare questions.

   Changes in populations of micro-organisms over a relatively short time period can provide helpful illustrations of the relationship between populations and resources.

   to identify patterns in data

   that a pyramid of numbers describes the numbers of food plants, herbivores and carnivores in a habitat

   that there is a flow of energy from the producer to the final organisms in the food chain

   Provide pupils with data on the numbers of animals and plants in a community and what they feed on. Ask them to count up numbers of producers, herbivores and carnivores, and to look for patterns in the results and to repeat for a different set of data. Ask pupils whether the pattern in the two sets of data is the same. Show them how to represent the data as a pyramid of numbers and explain the usefulness of this model in considering the interdependence of living things.

   Show pupils examples of inverted pyramids of numbers, eg involving an oak tree, and ask them to explain how these are different.

  draw pyramids of numbers from data provided

  explain how a pyramid of numbers describes the number of producers, herbivores and carnivores in a habitat

  describe how there is a flow of energy from the producer to the final organisms in the food chain

   Pupils will have considered energy transfer in unit 7I ‘Energy resources’.

   The term ‘trophic level’ is not required at this stage.

   Data on numbers of animals in the community studied in the field should be used for this activity, if available. This can then be built on using secondary data.

   KS3 Biology  Reviewing work

   to apply their knowledge of populations within a habitat to an environmental issue including protection of living things

   Present pupils with a case study, eg plans to cut down a number of trees in a school’s grounds. Provide relevant information, such as food webs for the community, population sizes, etc. Ask pupils to report how this action might affect the living things in the area including ideas they might have about protecting their local environment.

  produce a report in which consequences of the change are related to specific organisms within a particular habitat and how they might be protected

 

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 Doc Brown's Revision  KS3 Science KS3 BIOLOGY Unit 9A Inheritance and selection

KS3 Biology About the unit

In this unit pupils learn:

  that characteristics are inherited and how this is used in selective breeding

  why selective breeding is important

  about variations arising from environmental differences

In scientific enquiry pupils:

  decide what measurements are needed

  collect, organise and use large data sets relating to variation

  look for patterns in data

  evaluate the strength of evidence

  investigate the effect of selective breeding on a plant variety, taking account of variables that cannot be controlled

When teaching this unit, teachers should make reference to their school’s sex education policy and PSHE scheme. Teachers will be aware of the need for sensitivity to the personal circumstances of individual pupils and their families.

KS3 Biology Where the unit fits in

The unit builds on ideas introduced in unit 7A ‘Cells’, unit 7B ‘Reproduction’ and in unit 7D ‘Variation and classification’. This unit provides opportunities to revisit and revise topics met in other units in years 7 and 8. With some pupils, teachers may wish to concentrate on some of the new topics, extending activities, and with others to spend more time on revision of previous work.

The unit is closely related to unit 9D ‘Plants for food’, which considers environmental influences on food production.

There are opportunities for citizenship, PSHE and sex education to be linked to this unit.

The historical impact of scientific discovery is covered in unit 20 ‘Twentieth-century medicine’ and unit 21 ‘Scientific discoveries’ in the history scheme of work.

This unit lays the foundation for work in key stage 4 on inheritance and genetics.

KS3 Biology Expectations

At the end of this unit

in terms of scientific enquiry

most pupils will: select and make effective use of secondary sources of information about inheritance and selective breeding; plan how to collect, store and use data about a large number of individuals; use ICT to produce graphs and draw conclusions from these; evaluate the strength of evidence in relation to sample size and variation within the sample

some pupils will not have made so much progress and will: select information from secondary sources about inheritance and selective breeding; collect, store and use data about a large number of individuals; use ICT to produce graphs and identify patterns in these

some pupils will have progressed further and will: synthesise information about inheritance and selective breeding and identify limitations in the data assembled; decide whether the data collected about individuals is sufficient for firm conclusions

in terms of life processes and living things

most pupils will: identify some inherited characteristics and describe how some characteristics are influenced by environmental conditions; describe how sexual reproduction results in genetic information being inherited from both parents; identify characteristics in a plant or animal which are desirable in particular circumstances; outline how these characteristics might be passed on; suggest some of the issues to be considered in relation to selective breeding

some pupils will not have made so much progress and will: identify some inherited characteristics and some influenced by environmental conditions; describe sexual reproduction as the joining of two cells; identify some characteristics of an animal or plant which are desirable in particular circumstances

some pupils will have progressed further and will: describe how selective breeding can result in offspring with particular characteristics; recognise that asexual reproduction produces clones

KS3 Biology Prior learning

It is helpful if pupils know that:

  individuals of a species show characteristics which may be environmentally determined or inherited

  sexual reproduction involves the fusion of a male and female cell

KS3 Biology Health and safety

Risk assessments are required for any hazardous activity.

Model risk assessments used by most employers for normal science activities can be found in the publications listed in the Teacher’s guide. Teachers need to follow these as indicated in the guidance notes for the activities, and consider what modifications are needed for individual classroom situations.

KS3 Biology Language for learning

Through the activities in this unit pupils will be able to understand, use and spell correctly:

  words and phrases relating to inheritance, eg clone, gene, genetic information, gamete, genetically modified, selective breeding

  specialised words, eg clone, gene, gamete

  words with different meanings in scientific and everyday contexts, eg cell, variety

  words with similar but distinct meanings, eg variety, breed, species

  words and phrases relating to scientific enquiry, eg data set