Question

Define the term Double fertilization?


class 12th CBSE Biology sample paper

Answer 1

It is the participation of both the male gametes of male gametophyte. One fuses with egg to form diploid zygote. It is known as Syngamy .
The other male gamete fuses with two polar nuclei (or secondary nucleus) to form triploid primary endosperm nucleus (PEN).
It is known as triple fusion. The process of syngamy and syngamy and triple fusion constitute double fertilization.

Answer 2

Double fertilization occurs in the endosperm where the egg fertilizes the male gamete and the other two polar nuclei fuses with the haploid nucleus of male gametophyte.
For eg in coconut.