Question

Which statement best describes double fertilization?

	A.	One male nucleus fertilizes two polar nuclei.
	B.	One male nucleus fertilizes one egg cell and the other fertilizes two polar nuclei.
	C.	One male nucleus fertilizes one egg cell and the other fertilizes one female nucleus
	D.	Two male nuclei fertilize two haploid nuclei in the ovule.

Answer 1

SOLUTION :- Statement "B" best describes double fertilization and the statement is..

"One male nucleus fertilizes one egg cell and the other fertilizes two polar nuclei."

Explanation : (Double fertilization)

After entering one of the synergids (entery of pollen tube into embryo sac), the pollen tube releases two nucleus into cytoplasm of the synergid.

The following two events takes place in embryo sac :

1.. Syngamy

One male nucleus moves towards the egg cell and fuses with its nucleus.Thus, resulting in the formation of a diploid cell , the zygote.

2.. Triple fusion

The other male nucleus moves towards the two polar nuclei located in the central cell and fuses with them to produce a triploid primary endosperm nucleus (PEN).

This whole process is known as double fertilization.