Question

Double fertilisation is a process of fusion of

Answer 1

One male gamete fuses with the egg to give the diploid zygote; the other makes its way to the fusion nucleus in the central cell, already diploid, and by a second fusion gives a triploid primary endosperm nucleus, which is later concerned in… This process,double fertilization, occurs only in angiosperms.

Answer 2

double fertilization is a characterstic feature of angiosperms. in double fertilisation  two fusions occur .
The pollen releases two male gamete into the pollen tube which reaches embryo sac .
the first male gamete fuses with egg cell and forms zygote while  the other one fuses with polar nuclei to form polar endosperm nucleus which further develops into endosperm.
Thus we can say that DOUBLE FERTILISATION IS A PROCESS OF FUSION OF  TWO MALE GAMETES WITH POLAR NUCLEI AND EGG RESPECTIVELY. HOPE IT HELPS 
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