CBSE Class 10 Science 2022 · Paper 31(B)/6 · Question 14

(a) (i) The male part is the stamen (anther and filament; the anther makes the pollen grains). (ii) The female part is the pistil, or carpel (stigma, style and ovary; the ovary contains the ovules). (b) After fertilisation the zygote divides several times to form an embryo within the ovule. The ovule develops a tough coat and becomes a seed, and the ovary ripens into a fruit. (c)(i) Self-pollination is the transfer of pollen from the anther to the stigma of the same flower; it can take place without an outside agent and produces less variation. Cross-pollination is the transfer of pollen from one flower to the stigma of another flower, usually on another plant of the same species; it needs an agent such as wind, water, insects or birds, and, when the pollen comes from another plant, produces more variation. OR (c)(ii) The pollen grain that has landed on the stigma grows a pollen tube, which travels down through the style into the ovary and enters an ovule. The male germ cell carried by the tube fuses there with the female germ cell (egg); this fusion is fertilisation, and it forms the zygote.