Biology Theory (a) List four floral parts of a flower. (b) (i) In a tabular form, state…

(a) List four floral parts of a flower.

(b) (i) In a tabular form, state five differences between wind and insect pollinated flowers.
(ii) Give one example of each.

(c) (i) State three agents of fruit and seed dispersal.
(ii) Give an example of fruits or seeds dispersed by each agent

(d) (i) Define the term “hormones.
(ii) Name one plant hormone.
(iii) State two effects of plant hormones. 
 

Explanation

a(i) Four Floral parts of a flower are:
(1) calyx/sepals
(2) corollapetals
(3) androecium/stamen, filament, anther, pollen grains
(4) gynoecium/pistil/carpel
(5) stigma, style, ovary, pedicle, receptacle, ovules.

(b)(i) Differences between wind and insect pollinated flowers are: 

Wind pollinated flowers	Insect pollinated flowers
– Flowers are small or inconspicuous – No scent, odour or smell – No nectar – Have no particular shape – Flowers not brightly coloured – Produce large quantity of pollen grains – Smooth pollen grains – Pollen grains not sticky /powdery – Light pollen grains – Stigmas are large, feathery providing large surface area	-Flowers are large and conspicuous. -Scented/possess scent/odour -Nectar present -Flowers are specially shaped to facilitate pollination by particular types of insects. -Flowers are usually brightly coloured. -Produce relatively small quantity of pollen grains -Rough pollen grains /Spiky pollen grains -Pollen grain are not light/heavy -Stigmas are flat/have small surface area

(b)(ii)Examples of wind pollinated flowers are Maize, Millet, Rice, Oat, Grass while examples of insect pollinated flowers are Delonix, Tridax, Eurena, Sunflower, Basam, Mango, Pride of Barbados, Thumbergia, Hibiscus.

(c) Agents of fruit and seed dispersal are:

(i) Wind – tecons,cotton, tridax, aspilia, emilia etc.

(ii) Animal-mango, pawpaw, oranges etc.

(iii) Explosive mechanism – flamboyant, pride of barbados, okra, oil bean, castor oil seed, balsam etc.

(iv) Man – Cocoa, rubber, oil palm, cassava, coconut, etc (v) Water coconut, mangrove, water-lily, etc.

(d)(i) Hormones are organic/chemical susbtances/bio chemical substances produced in minute quantities in one part of an organism and transported to the site of action where they exact specific effect to control body metabolism.

(ii) Examples of plant hormones are Indole  -3- acetic acid/Indole acetic acid (I AA), Gibberellin, Florigen, Cytokinins, Put Abscussin/abscissic acid, Traumatin 2,4, dicholorphencxy ethanoic acid ( 2- 4 -d) auxin.

(iii) Examples of effects of plant hormones are; 

(1) Promotes abscission of leaves.

(2) Induces dormancy in buds/seeds.

(3) Promotes ripening of fruits/maturity/flowering.

(4) Encourages parthenocarpy

(5) Promotes apical dominance

(6) Promotes growth

(7) Excess inhibits growth in root/ it retards growth in roots when in excess/high concentration

(8) delays abscission in young leaves