(3a) Fertilisation

Fertilisation involves the joining of the male and females plant cells.

After a pollen grain has landed on a ripe stigma the formation of a pollen tube is triggered (diagram on right).

The pollen tube grows down from the stigma through the style to the ovary.

The male nucleus is conveyed down the pollen tube to the ovary.

The male nucleus then joins with the female sex cell inside an ovule to complete the fertilisation process.

Therefore, genetically, when the two nuclei join together, the completed fertilisation is 2 gametes ==> zygote, a complete set of chromosomes.

---

(3b) Formation of seed and fruit

After fertilisation the ovule, inside the ovary, develops into the seed.

Every seed contains a dormant embryo plant (dormant means inactive).

The embryonic plant has a food store which it can utilise when conditions are right for it to grow - the process of germination.

The ovary develops into a fruit structure around the seed.

Plants produce many seeds because do not germinate and grow into healthy plants.

---

Key points on sexual reproduction in flowering plants

Source of information is based on textbooks and syllabus-specifications for students taking the AQA GCSE, Edexcel GCSE and OCR GCSE level biology examinations (~US grades 9-10)

Revision notes on sexual reproduction in flowering plants, covering fertilisation.

---

Sexual Reproduction in Flowering Plants

Sexual reproduction in plants involves the fusion of male and female gametes to produce a seed, which can grow into a new plant.

This process includes pollination, fertilisation, and the formation of seeds and fruits.

---

1. Fertilisation in Flowering Plants

Step-by-step process:

1. Pollination occurs – pollen (male gamete) is transferred from the anther to the stigma.

2. Pollen grain germinates – on the stigma, forming a pollen tube.

3. Pollen tube grows down the style toward the ovary, using enzymes to digest its way.

4. Nucleus of the male gamete travels down the pollen tube to reach the ovule in the ovary.

5. Fertilisation takes place – the male nucleus fuses with the female nucleus (in the ovule), forming a zygote.

---

2. Development After Fertilisation

What each part becomes:

---

3. Structure of a Mature Seed

• Embryo: Will grow into the new plant (contains future root and shoot)

• Cotyledons: Food store (especially in dicot seeds)

• Testa: Tough seed coat that protects the embryo

• Micropyle: Small hole in the seed coat allowing water entry during germination

---

4. Role of Fruits

• Fruits protect seeds while they develop.

• Aid in seed dispersal – e.g. by animals, wind, or water.

• Some fruits (like berries) are fleshy and sweet to attract animals; others (like nuts or pods) are hard and dry.

---

Quick Recap

• Fertilisation = fusion of gametes inside the ovule

• Ovule → Seed, Ovary → Fruit

• Seeds contain the embryo and stored food, protected by a testa

• Fruits help in protecting and spreading seeds

---

Keywords, phrases and learning objectives for this part on flowering plants

Be able to describe and interpret from a diagram the process of fertilisation in flowering plants.

The details should include the male nucleus fusing with an egg cell and the development of seeds or fruit in flowering plants.

Know that embryo remains dormant until conditions are right to germinate and the plant grows and develops to maturity.

---

WHAT NEXT?

TOP OF PAGE

INDEX of biology notes on flowering plants

INDEX of all my BIOLOGY NOTES

BIG website, try using the [SEARCH BOX], maybe quicker than the many indexes!

Basic Science Quizzes for UK KS3 science students aged ~12-14, ~US grades 6-8

Biology * Chemistry * Physics for UK GCSE level students aged ~14-16, ~US grades 9-10

Advanced Level Chemistry for pre-university age ~16-18 ~US grades 11-12, K12 Honors

Find your GCSE/IGCSE science course for more help links to all science revision notes

email doc brown - comments - query?

---

Revision notes on xyz based on the syllabus-specifications for students taking IGCSE/GCSE level biology examinations, summary revision notes and key points on xyz for students taking the AQA igcse/gcse biology notes on xyz, Edexcel gcse biology notes on xyz,  OCR 21st century GCSE biology notes on xyz, OCR gateway GCSE biology notes on xyz, WJEC gcse biology notes on xyz, CCEA gcse biology notes on xyz for students taking CIE Cambridge igcse biology, exam revision notes on xyz, useful for US grade 9-10 biology courses, importance of explaining fertilisation in sexual reproduction of plants in GCSE level biology, What you need to know about explaining fertilisation in sexual reproduction of plants for GCSE level biology, Explaining the use of explaining fertilisation in sexual reproduction of plants knowledge in GCSE level biology, Examples of explaining fertilisation in sexual reproduction of plants explained when studying GCSE level biology, What is significant about explaining fertilisation in sexual reproduction of plants, describing the theory of explaining fertilisation in sexual reproduction of plants when studying GCSE level biology, revision notes for explaining fertilisation in sexual reproduction of plants in exams, online exam help for explaining fertilisation in sexual reproduction of plants, revision notes about explaining fertilisation in sexual reproduction of plants, what do I need to learn about explaining fertilisation in sexual reproduction of plants for by GCSE biology exam? help to understand the explaining fertilisation in sexual reproduction of plants topic in preparation for GCSE biology exam question, how to prepare for questions involving explaining fertilisation in sexual reproduction of plants in a GCSE biology examination?

---