Question

Trace the events that would take place in a flower from the time pollen grain of the same species fall on the stigma up to the completion of fertilisation.

Answer 1

when the pollen grains comes to stigma by pollination or cross pollination it sticks to it and secrets a chemical.This chemical produces a pollen tube which contains a male gamete .this gamete enters to ovary and it selects one ovule out of six.then fertilization starts and a zygote is formed

Answer 2

1.The pollen grain sticks to the stigma and attached to it
2.a small growth is seen in pollen as germ tube and grows as a pollen tube
3. the nucleus of the pollen travels through the tube
4. nucleus divides mitotically into two male garment.
5. male gamete enters to the embryo sac.