Question

proper definition and well defined process of double fusion and triple fertilisation. Please help it's urgent

Answer 1

Double fusion is the process in which two male gametes fuse with the one egg (female gamete) and the secondary nucleus respectively to form the zygote and the endosperm.

Triple fertilization is the process involving fusion of two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

Answer 2

double fusion :- Fusion of 2 male hamare, one with egg cell anther with polar nuclei. It results in formation of double fertilisation and endosperm
Triple Fusion:- It is a result of fusion of 3 cells i.e. 2 polar cells and 1 male nuclei. It results in formation of endosperm.