Question

(a) Explain the terms 'self pollination' and 'cross-pollination'?
(b) How do the insects help in cross-pollination?
(c) How is the process of pollination different from fertilization?

Answer 1

Answer:

1. Self-pollination occurs when the pollen from the anther is deposited on the stigma of the same flower, or another flower on the same plant. Cross-pollination is the transfer of pollen from the anther of one flower to the stigma of another flower on a different individual of the same species.
2. Insects moves from flower to flower to suck nectar. When an insect sits on the flower of a plant, pollen grains from the anther of this flower get attached to its body. Thus, insects help in cross-pollination.
3. Pollination is the act of transferring pollen from the male parts of a flower (the anther) to the female parts of the flower (this is the stigma in the first instance). Fertilisation occurs when a male gamete of any sexually reproducing organism combines with the female gamete to form a zygote.

Answer 2

Answer:

Pollination is defined as the process of transfer of pollens from anther to stigma. The process takes place with the help of pollinators like air, water and some insects.

Fertilization is defined as the fusion of male and female gametes. It takes place in the ovule and leads to the formation of zygote.