(a) Draw a neat labelled diagram of the longitudinal section of a flower, labelling any four reproductive parts.
(b) Define pollination and fertilisation. State one difference between them.
(c) Trace the fate of the ovule and the ovary after fertilisation in a flowering plant.
Generated by claude-sonnet-4-6 · 2026-06-26 01:01 · grounding rag
Model Answer
(a) Labelled Diagram – Longitudinal Section of a Flower:
(Draw a bisexual flower showing the following labelled parts)
Four reproductive parts to label:
- Anther (produces pollen grains)
- Filament (together with anther = stamen)
- Stigma (receives pollen)
- Style
- Ovary (contains ovules)
- Ovule (contains egg cell)
(Label any four of the above reproductive parts on your diagram.)
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(b) Definitions and Difference:
Pollination: Transfer of pollen grains from the anther to the stigma of a flower.
Fertilisation: The fusion of the male germ-cell (from pollen) with the female germ-cell (egg) present in the ovule to form a zygote.
| | Pollination | Fertilisation |
|---|---|---|
| Nature | Transfer of pollen | Fusion of gametes |
Difference: Pollination is a physical transfer process; fertilisation is the actual fusion of male and female gametes forming a zygote.
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(c) Fate after Fertilisation:
- The ovule develops a tough coat and is converted into a seed, which contains the embryo.
- The ovary grows, ripens, and develops into a fruit.
- Petals, sepals, stamens, style and stigma shrivel and fall off.
Source: How do Organisms Reproduce, Section 7.3.2
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Explanation
- The diagram is worth marks; draw clearly and label neatly — examiners award marks for each correct label.
- Define pollination and fertilisation in one sentence each; the difference must be explicit.
- For part (c), remember the two key conversions: ovule → seed and ovary → fruit. These are direct, frequently tested facts from the textbook.