3 Understand the structure and function of flowers fruits and seeds

Question 1

3. 1.1 State the functions of flowers:
4. 1.2 Draw a vertical section of a monocotyledon flower (not grass) and a dicotyledon flower to show where appropriate:
5. receptacle,
6. tepal,
7. sepal,
8. petal,
9. calyx,
10. corolla,
11. nectary,
12. anther,
13. filament,
14. stamen,
15. stigma,
16. style,
17. ovary
18. ovule
19. 1.3 State the meaning of ‘monoecious’ and ‘dioecious’ in relation to plants. Know TWO examples of each.
20. 1.4 State the meaning of the term ‘pollination’.
21. 1.5 Describe the characteristics of wind and bee pollinated plants - variations in flower structure and pollen

Answer 1

3. 1 To aid pollination, give rise to seeds and fruits.
4. 1.3

Monoecious

produce separate male and female flowers on the same plant

This encourages cross-pollination between adjacent plants while still allowing self-pollination if the plant is isolated from those of the same species

Zea mays and Corylus avellana .

Dioecious

produce separate male and female flowers on different plants.

Self-pollination is impossible in such plants but the number of dioecious plant species is very few

Ilex aquifolium and Skimmia japonica

Question 2

3. 2.1 State the meaning of the term ‘fertilisation’ - fusion of a male gamete from pollen with a female gamete in the ovule to produce the embryo.
4. 2.3 State the meaning of the terms ‘fruit’ and ‘seed’ - a fruit is formed from the ovary after fertilisation. A seed is formed from the ovule after fertilisation.
5. 2.4 State the function of fruits and seeds - Fruit: distribution and protection of the seed and may impose dormancy. Seed: distribution and protection of the embryo, may impose dormancy, gives rise to new plants.
6. 2.5 Describe the means by which seeds are dispersed - wind: (wing, parachute and censer (Papaver)); water*; explosive; animals: (attachment, scatter hoarding and frugivory).

TWO plant examples for EACH of the above except where indicated

* where only ONE is required.

3.2.6 Describe the internal and external structure of the seed and state the function of the various parts: testa, cotyledon, embryo, radicle, plumule, hypocotyl, epicotyl, endosperm, hilum, micropyle.

Examples to be studied to include French bean (Phaseolus vulgaris) and broad bean (Vicia faba).

3.2.7 Describe ONE example of epigeal germination and ONE example of hypogeal germination, germination of French bean (Phaseolus vulgaris), and broad bean (Vicia faba).