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Revision help links for separate Gateway science OCR GCSE 9-1 Biology PAPER 1
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Revision help for the separate science 9-1 OCR Gateway Science A GCSE 9-1 BIOLOGY A 1st Exam paper - learning objectives for exam papers OCR Level 1/2 GCSE (Grade 9-1) in Biology A (Gateway Science) (J247) Foundation Tier Paper 1/Higher Tier Paper 3 - OCR (Grade 9-1) Gateway GCSE Biology A Topic B1 "Cell level systems", Topic B2 "Scaling up", Topic B3 "Organism level systems", Topic B7 "Practical skills" for Gateway 2020 GCSE biology exam papers onwards (re-edit) LINK for OCR Gateway Science GCSE BIOLOGY A 2nd paper B1-B7 LINK GCSE Gateway Combined Science biology 1st paper B1-3, CS7 LINK GCSE Gateway Combined Science biology 2nd paper B1-6, CS7 This is a BIG website, you need to take time to explore it [SEARCH BOX] Use your mobile phone in 'landscape' orientation See also OCR 21st Century Sciences B Revision Links email doc brown - query? or comment? For ALL other exam papers, use and bookmark the link below PLEASE READ CAREFULLY THE FOLLOWING POINTS before using my OCR Gateway 9-1 GCSE science pages
Syllabus-specification CONTENT INDEX of revision summary notes (OCR GCSE Gateway science suite biology) Revision summary for OCR Gateway Science GCSE 9-1 BIOLOGY A FT Paper 1/HT Paper 3 (this page) What is assessed in this paper? (for OCR 9-1 GCSE Gateway separate science GCSE BIOLOGY) The 1st biology paper assesses Topics B1, B2, B3 and B7 SUMMARY of Topic B1: Cell level systems: Containing sections: B1.2 What happens in cells (and what do cells need)? SUMMARY of Topic B2: Scaling up: Containing sections SUMMARY of Topic B3: Organism level systems: Containing sections B3.1 Coordination and control – the nervous system B3.2 Coordination and control – the endocrine system, B3.3 Maintaining internal environments Revision of B7 Practical skills
Revision summary for OCR Gateway Science GCSE 9-1 BIOLOGY A FT Paper 2/HT Paper 4 (separate page) What is assessed in this paper? (for OCR 9-1 GCSE Gateway separate science GCSE BIOLOGY) The 2nd biology paper assesses Topics B4, B5, B6 and B7, BUT assumes knowledge of Topics B1, B2, B3 SUMMARY of Topic B4: Community level systems: Containing sections SUMMARY of Topic B5: Genes, inheritance and selection: Containing sections B5.2 Natural selection and evolution SUMMARY of Topic B6: Global challenges: Containing sections B6.1 Monitoring and maintaining the environment, B6.3 Monitoring and maintaining health Revision of Topic B7 Practical skills The 2nd biology paper assesses Topics B4, B5, B6 and B7, BUT assumes knowledge of Topics B1, B2, B3 Biology Key Ideas (for OCR GCSE 9-1 Gateway Science GCSE BIOLOGY A 1st paper) Biology is the science of living organisms (including animals, plants, fungi and microorganisms) and their interactions with each other and the environment. The study of biology involves collecting and interpreting information about the natural world to identify patterns and relate possible cause and effect. Biological information is used to help humans improve their own lives and strive to create a sustainable world for future generations. You should understand how, through the ideas of biology, the complex and diverse phenomena of the natural world can be described in terms of a small number of key ideas which are of universal application, and which can be illustrated in the separate topics set out below. These ideas include:
Topic B1: Cell level systems (OCR GCSE Gateway science suite biology) (OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B1 "Cell level systems", FT Paper 1/HT Paper 3) B1.1 Cell structures (OCR GCSE Gateway science suite biology) (OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B1 "Cell level systems", FT Paper 1/HT Paper 3) Know that cells are the fundamental units of living organisms. Cells contain many sub-cellular structures that are essential for the functioning of the cell as a whole. Microscopy is used to examine cells and sub-cellular structures. You should be familiar with cells as the fundamental unit of living organisms, and with the use of light microscopes to view cells. You should also be familiar with some sub-cellular structures, and the similarities and differences between plant and animal cells You should appreciate that cells have a 3D structure - they are not flat!. B1.1a Be able to describe how light microscopes and staining can be used to view cells including lenses, stage, lamp, use of slides and cover slips, and the use of stains to view colourless specimens or to highlight different structures/tissues and calculation of the magnification used. You should have investigated of a range of plant and animal cells using light microscope, pictures, light micrographs and diagrams and measure the size and magnification of the cells. You should have prepared cheek cell and onion epidermis cell slides. B1.1b Be able to explain how the main sub-cellular structures of eukaryotic cells (plants and animals) and prokaryotic cells are related to their functions including nucleus, genetic material, chromosomes, plasmids, mitochondria (contain enzymes for cellular respiration), chloroplasts (contain chlorophyll) and cell membranes (contain receptor molecules, provides a selective barrier to molecules). You should have made 3D model plant and animal cells to illustrate their differences. You should have investigated cytoplasmic streaming in Elodea spp. B1.1c Be able to explain how electron microscopy has increased our understanding of sub-cellular structures including increased resolution in a transmission electron microscope. You should have compared of a range of cells using pictures from light and electron micrographs. You should have compared of the visible structures visible on light and electron micrographs. Microscopy - the development and use of microscopes in biology Introduction to plant and animal cell structure and function
B1.2 What happens in cells (and what do cells need)? (OCR GCSE Gateway science suite biology) (OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B1 "Cell level systems", FT Paper 1/HT Paper 3) Appreciate that life processes depend on biological molecules whose structure is related to their function. Inside every cell is genetic material and this is used as a code to make proteins. Enzymes are important proteins in biology. You should have a simple understanding of the double helix model of DNA. You should be familiar with the idea of enzymes as biological catalysts. Appreciate that DNA is NOT made of protein or sugar. You must not assume that all enzymes have an optimum temperature of 37°C (human body temperature). You need to be able to carry out rate calculations for chemical reactions. B1.2a Be able to describe DNA as a polymer You should have made 3D models of DNA to illustrate its structure. B1.2b Be able to describe DNA as being made up of two strands forming a double helix B1.2c (HT only) Be able to describe that DNA is made from four different nucleotides; each nucleotide consisting of a common sugar and phosphate group with one of four different bases attached to the sugar - noting the pairs of complementary bases (A-T and G-C) You should have made 3D models of DNA to illustrate its structure.
B1.2d (HT only) Be able to recall a simple description of protein synthesis the unzipping of the DNA molecule containing the gene, copying to mRNA in nucleus (transcription), (translation) of the nucleotide sequence, in the cytoplasm. You should have compared transcription and translation to a non-lending library. B1.2e (HT only) You should be able to explain simply how the structure of DNA affects the proteins made in protein synthesis triplet code and use of a triplet code to determine amino acid order in a protein DNA structure and Protein Synthesis B1.2f Be able to describe experiments that can be used to investigate enzymatic reactions You should have investigated enzyme activity, including numerical analysis of data and graphical representation of results. B1.2g Be able to explain the mechanism of enzyme action including the role of enzymes in metabolism - the role of the active site, enzyme specificity (lock and key hypothesis) and factors affecting the rate of enzyme controlled reactions (pH, temperature, substrate and enzyme concentration) You should have seen the demonstration of the effect of amylase on a baby rice paste. You should have investigated enzyme controlled reactions. ENZYMES - structure, function, optimum conditions, investigation experiments See also Enzymes and Biotechnology
B1.3 Respiration (OCR GCSE Gateway science suite biology) (OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B1 "Cell level systems", FT Paper 1/HT Paper 3) Metabolic processes such as respiration are controlled by enzymes. Organic compounds are used as fuels in cellular respiration to allow the other chemical reactions necessary for life. You should also have some underpinning knowledge of respiration. This should include that respiration involves the breakdown of organic molecules to enable all the other chemical processes necessary for life. You should be able to recall the word equation for respiration. Common misconceptions - ventilation is respiration and don't get confused between the terms breakup and breakdown. B1.3a Be able to describe cellular respiration as a universal chemical process, continuously occurring that supplies ATP in all living cells B1.3b Be able to describe cellular respiration as an exothermic reaction Demonstration of an exothermic reaction (e.g. heat pack). B1.3c Be able to compare the processes of aerobic and anaerobic respiration - in plants/fungi and animals the different conditions, substrates, products and relative yields of ATP Research into whether plants respire. You should have investigated of fermentation in fungi. You should have investigated of respiration in yeast using alginate beads to immobilise the fungus. RESPIRATION - aerobic and anaerobic in plants, fungi and animals, conditions, substrates etc. B1.3d Be able to explain the importance of sugars in the synthesis and breakdown of carbohydrates to include use of the terms monomer and polymer Demonstration of the synthesis and breakdown of biological molecules (e.g. using Lego bricks). B1.3e Be able to explain the importance of amino acids in the synthesis and breakdown of proteins to include use of the terms monomer and polymer (amino acid and protein). B1.3f Be able to explain the importance of fatty acids and glycerol in the synthesis and breakdown of lipids See also Enzymes - section on digestion and synthesis
B1.4 Photosynthesis (OCR GCSE Gateway science suite biology) (OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B1 "Cell level systems", FT Paper 1/HT Paper 3) Know that Life processes depend on photosynthesis. Green plants and algae trap light from the Sun to fix carbon dioxide with hydrogen from water making organic compounds. You should also have some underpinning knowledge of photosynthesis. You should have an understanding that plants make carbohydrates in their leaves by photosynthesis, and be able to recall the word equation for photosynthesis. Appreciate that plants do respire too!. Be able to understand and use inverse proportion – the inverse square law and light intensity in the context of factors affecting photosynthesis B1.4a Be able to describe photosynthetic organisms as the main producers of food and therefore biomass for life on Earth B1.4b Be able to describe the process of photosynthesis - reactants and products, location of the reaction (in the chloroplasts. Investigation of photosynthesis e.g. the Priestley experiment using Cabomba experiment to collect oxygen or the Ingenhousz experiment to show mass gain. B1.4c Be able to describe photosynthesis as an endothermic reaction Demonstration of an endothermic reaction (e.g. icepack). B1.4d Be able to describe experiments to investigate photosynthesis. Experiments to show the consequences of light exclusion on photosynthesising plants (e.g. testing geraniums for presence/absence of starch). B1.4e Be able to explain the effect of temperature, light intensity and carbon dioxide concentration on the rate of photosynthesis You should have investigated of photosynthesis in algae using alginate beads to immobilize the algae. B1.4f (HT only) Be able to explain the interaction of these factors in limiting the rate of photosynthesis Photosynthesis, importance explained, limiting factors affecting rate, leaf adaptations
Topic B2: Scaling up (OCR GCSE Gateway science suite biology) (OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B2 "Scaling up", FT Paper 1/HT Paper 3) Know that cells transport many substances across their membranes by diffusion, osmosis and active transport. Stem cells are found in both plants and animals. These stem cells can divide, differentiate and become specialised to form tissues, organs and organ systems. You should be familiar with the role of diffusion in the movement of materials in and between cells. Common misconceptions You may show some confusion regarding surface area : volume ratio, particularly how larger animals have a smaller surface area : volume ratio. There is some confusion as to stem cells: where they are found and their roles. Take care to give clear definitions - an important general rule! B2.1a Be able to explain how substances are transported into and out of cells through diffusion, osmosis and active transport including examples of substances moved, direction of movement, concentration gradients and use of the term water potential (no mathematical use of water potential required) Observation of osmosis in plant cells using a light microscope. Demonstration of ‘creaming yeast’ to show osmosis. Investigating of changes in mass of vegetable chips when placed in sucrose/salt concentrations of varying concentrations. Diffusion, osmosis and active transport Examples of surfaces for the exchange of substances in animal organisms B2.1b Be able to describe the process of mitosis in growth, including the cell cycle including the stages of the cell cycle as DNA replication, movement of chromosomes, followed by the growth of the cell Modelling of mitosis using everyday objects e.g. shoes, socks etc. Observation of mitosis in stained root tip cells. CELL DIVISION - cell cycle - mitosis, meiosis and sexual reproduction, binary fission B2.1c Be able to explain the importance of cell differentiation including the production of specialised cells allowing organisms to become more efficient and examples of specialised cells.
An introduction to cell specialisation B2.1d Be able to recall that stem cells are present in embryonic and adult animals and meristems in plants
B2.1e Be able to describe the functions of stem cells including the division to produce a range of different cell types for development, growth and repair B2.1f Be able to describe the difference between embryonic and adult stem cells in animals.
Stem cells and an introduction to cell specialisation
B2.2 The challenges of size (OCR GCSE Gateway science suite biology) (OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B2 "Scaling up", FT Paper 1/HT Paper 3) Know that when organisms become multicellular, the need arises for highly adapted structures including gaseous exchange surfaces and transport systems, enabling living processes to be performed effectively. You should be familiar with the role of diffusion in the movement of materials in and between cells. You should also be familiar with the human gaseous exchange system. Common misconceptions You have a view that the slow flow of blood in capillaries is due to the narrow diameter, when in fact it is a function of the total cross-sectional area of the capillaries (1000 times greater than the aorta). Be able to explain the importance of the slow flow of blood in allowing time for exchange by diffusion, this misunderstanding should be considered. B2.2a Be able to explain the need for exchange surfaces and a transport system in multicellular organisms in terms of surface area : volume ratio to include surface area, volume and diffusion distances Investigating surface area : volume ratio using hydrochloric acid and gelatine cubes stained with phenolphthalein or other suitable pH indicator. B2.2b Be able to describe some of the substances transported into and out of a range of organisms in terms of the requirements of those organisms - oxygen, carbon dioxide, water, dissolved food molecules, mineral ions and urea Diffusion, osmosis and active transport Examples of surfaces for the exchange of substances in animal organisms B2.2c Be able to describe the human circulatory system to include the relationship with the gaseous exchange system, the need for a double circulatory system in mammals and the arrangement of vessels Modelling of the human circulatory system. B2.2d Be able to explain how the structure of the heart and the blood vessels are adapted to their functions including the structure of the mammalian heart with reference to valves, chambers, cardiac muscle and the structure of blood vessels with reference to thickness of walls, diameter of lumen, presence of valves Investigating heart structure by dissection. You should have investigated a blood smear using a light microscope. Modelling of blood using sweets to represent the components. B2.2e Be able to explain how red blood cells and plasma are adapted to their transport functions in the blood. Examine the gross structure of blood vessels using a light microscope. Investigating of the elasticity of different blood vessels using hanging masses. B2.2f Be able to explain how water and mineral ions are taken up by plants, relating the structure of the root hair cells to their function Examination of root hair cells using a light microscope. Demonstration of the effectiveness of transpiration by trying to suck water from a bottle using a 10m straw. You should have investigated of the position of the xylem/phloem in root, stem and leaf tissues using a light microscope. Interpretation of experimental evidence of the movement of dissolved food materials in a plant. Microscopy - the development and use of microscopes in biology - optical and electron B2.2g Be able to describe the processes of transpiration and translocation including the structure and function of the stomata Measurement of plant stomatal density by taking an impression of the leaf using clear nail varnish or spray on plaster. B2.2h Be able to explain how the structure of the xylem and phloem are adapted to their functions in the plant B2.2i Be able to explain the effect of a variety of environmental factors on the rate of water uptake by a plant - light intensity, air movement, and temperature Interpreting experimental evidence of investigations into environmental factors that affect water uptake. B2.2j Be able to describe how a simple potometer can be used to investigate factors that affect the rate of water uptake. You should have investigated of transpiration rates from a plant cutting. Work out the rate of transpiration in volume of water/time. Diffusion, osmosis, active transport, exchange of substances - examples fully explained
Topic B3: Organism level systems (OCR GCSE Gateway science suite biology) (Revision for OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B3 "Organism level systems", FT Paper 1/HT Paper 3) B3.1 Coordination and control – the nervous system (OCR GCSE Gateway science suite biology) Know that the human nervous system is an important part of how the body communicates with itself and also receives information from its surroundings. You should have a concept of the hierarchical organism of multicellular organisms from cells to tissues to organs to systems to organisms. Common misconceptions You commonly think that their eyes see objects ‘directly’, like a camera, but the reality is that the image formed by the brain is based on the eyes and brains interpretation of the light that comes into the eye i.e. different people will perceive the same object or image differently. You may have the misconception that some sort of “force” comes out of the eye, enabling it to see. B3.1a Be able to describe the structure of the nervous system CNS including sensory and motor neurones and sensory receptors You should have made 3D models of neurones to illustrate their structure. B3.1b Be able to explain how the components of the nervous system can produce a coordinated response - it goes to all parts of the body, has many links, has different sensory receptors and is able to coordinate responses. Demonstration (by video) of someone trying to do everyday tasks whilst being given mild electric shocks (Brainiac). B3.1c Be able to explain how the structure of a reflex arc is related to its function. Demonstration of reaction time by getting a learner to catch a falling £5 note. Research into reflexes. (Investigating of reaction times by ruler drop). An introduction to the nervous system including the reflex arc B3.1d Be able to explain how the main structures of the eye are related to their functions including cornea, iris, pupil, lens, retina, optic nerve, ciliary body, suspensory ligaments Demonstration of the inversion of an image through a beaker full of water. Demonstration of the features of the human eye. You should have investigated of eye structure by dissection. B3.1e Be able to describe common defects of the eye and Be able to explain how some of these problems may be overcome including colour blindness, short-sightedness and long-sightedness. Measurement of focal length in a variety of situations. Research into eye defects, their diagnosis and treatment. Optics - lenses (convex, concave, uses), experiments, ray diagrams, correction of eye defects gcse physics notes The eye - structure and function - correction of vision defects B3.1f Be able to describe the structure and function of the brain cerebrum, cerebellum, medulla, hypothalamus, pituitary The BRAIN - what the different parts do and the dangers if damaged B3.1g (HT only) Be able to explain some of the difficulties of investigating brain function to include the difficulty in obtaining and interpreting case studies and the consideration of ethical issues Discussion of problems associated with brain research including the difficulty in getting research subjects. B3.1h (HT only) Be able to explain some of the limitations in treating damage and disease in the brain and other parts of the nervous system to include limited ability to repair nervous tissue, irreversible damage to the surrounding tissues, difficulties with accessing parts of the nervous system Research into a study of brain injury. The BRAIN - what the different parts do and the dangers if damaged
B3.2 Coordination and control – the endocrine system (OCR GCSE Gateway science suite biology) (Revision for OCR Gateway Science GCSE 9-1 BIOLOGY A, Topic B3 "Organism level systems", FT Paper 1/HT Paper 3) Know that hormones are chemical messengers. In animals, hormones are transported around the body in the blood and affect target tissues and organs. Hormones have a variety of roles in the human body, including controlling reproduction. Plant hormones are chemicals that regulate plant growth and development. You can be used in agriculture to control the rate of growth. You should be aware of a number of hormones including adrenaline and the male and female sex hormones. Common misconceptions In the menstrual cycle, you may have problems relating the time of conception to the condition of the lining of the uterus. B3.2a Be able to describe the principles of hormonal coordination and control by the human endocrine system including use of chemical messengers, transport in blood, endocrine glands and receptors B3.2b (HT only) Be able to explain the roles of thyroxine and adrenaline in the body - thyroxine as an example of negative feedback system Hormone systems - Introduction to the endocrine system - adrenaline & thyroxine hormones B3.2c Be able to describe the role of hormones in human reproduction including the control of the menstrual cycle including oestrogen, progesterone, FSH and testosterone. Hormone Systems - menstrual cycle B3.2d (HT only) Be able to explain the interactions of FSH, LH, oestrogen and progesterone in the control of the menstrual cycle Analysis of relative hormones levels from raw data and graphically. B3.2e Be able to explain the use of hormones in contraception and evaluate hormonal and non-hormonal methods of contraception including relative effectiveness of the different forms of contraception. Discussion into the various methods of contraception and their effective/ethical use. Hormone systems - menstrual cycle, contraception, fertility treatments B3.2f (HT only) Be able to explain the use of hormones in modern reproductive technologies to treat infertility. Research into Xenopus laevis pregnancy testing to detect hCG by the stimulation of oogenesis. Research into hormonal treatments for infertility Hormone systems - menstrual cycle, contraception, fertility treatments B3.2g Be able to explain how plant hormones are important in the control and coordination of plant growth and development, with reference to the role of auxins in phototropisms and gravitropisms - unequal distribution of auxin You should have investigated of the effects of phototropism using seedlings. B3.2h Be able to describe some of the variety of effects of plant hormones, relating to auxins, and (HT only) gibberellins and ethene controlling growth, controlling germination, fruit ripening, flower opening and shedding of leaves You should have investigated/research into the question “does one bad banana spoil the fruit bowl?” B3.2i (HT only) Be able to describe some of the different ways in which people use plant hormones to control plant growth - selective herbicides, root cuttings, seedless fruit (parthenocarpic fruit development), altering dormancy Hormone control in plants and uses of plant hormones
B3.3 Maintaining internal environments (OCR GCSE Gateway science suite biology)
Know that homeostasis is crucial to the regulation of internal environments and enables organisms to adapt to change, both internally and externally. Internal temperature, blood sugar levels and osmotic balance are regulated by a number of organs and systems working together. You will build on the knowledge and understanding gained in section 3.1 about coordination and control when considering the topics in this section. Don't confuse type 1 and type 2 diabetes, and the effective treatments for each. The effect of ADH on the permeability of the kidney tubules is often confused. B3.3a Be able to explain the importance of maintaining a constant internal environment in response to internal and external change - allowing metabolic reactions to proceed at appropriate rates Research into hypothermia. B3.3b Be able to describe the function of the skin in the control of body temperature detection of external temperature, sweating, shivering, change to blood flow
Homeostasis - thermoregulation, control of temperature B3.3c Be able to explain how insulin controls blood sugar levels in the body B3.3d (HT only) Be able to explain how glucagon interacts with insulin to control blood sugar levels in the body You should have investigated into the glucose content of fake urine to diagnose diabetes, using e.g. Clinistix. B3.3e Be able to compare type 1 and type 2 diabetes and be able to explain how they can be treated Homeostasis - control of blood sugar level - insulin and diabetes Keeping healthy - non-communicable diseases - risk factors B3.3f Be able to explain the effect on cells of osmotic changes in body fluids higher, lower or equal water potentials leading to lysis or shrinking (no mathematical use of water potentials required) Demonstration of the different water potentials on different cells. B3.3g Be able to describe the function of the kidneys in maintaining the water balance of the body varying the amount and concentration of urine and hence water excreted You should have investigated of the structure of the structure of a kidney by dissection and the application of H2O2 to visualise the nephrons. You should have investigated into the glucose content of fake urine to diagnose diabetes, using e.g. Clinistix. B3.3h Be able to describe the gross structure of the kidney and the structure of the kidney tubule B3.3i (HT only) Be able to describe the effect of ADH on the permeability of the kidney tubules amount of water reabsorbed and negative feedback You should have investigated of the different sections of a nephron and the composition of the filtrate from each area. B3.3j (HT only) Be able to explain the response of the body to different temperature and osmotic challenges to include high sweating and dehydration, excess water intake, high salt intake responses to include mechanism of kidney function, thirst Research into sports’ drinks and evaluation into which is best for athletes. Homeostasis - thermoregulation, control of temperature B7 Practical skills
ALL OCR GCSE (Grade 9-1) Level 1/Level 2 GATEWAY SCIENCE A specifications and syllabus revision summary links OCR (Grade 9-1) GCSE Gateway science BIOLOGY A 1st GCSE BIOLOGY paper (separate science Topics B1-3) OCR (Grade 9-1) GCSE Gateway science BIOLOGY A 2nd GCSE BIOLOGY paper (separate science Topics B4-6) OCR (Grade 9-1) GCSE Gateway science PHYSICS A 1st GCSE PHYSICS paper (separate science Topics P1-4) OCR (Grade 9-1) GCSE Gateway science PHYSICS A 2nd GCSE PHYSICS paper (separate science Topics P5-8) Watch out for HT Only sections AND make sure you know exactly which GCSE science course you are doing! See also OCR 21st Century Sciences B Revision Links
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