What do you understand by double fertilisation?
In angiosperms both the male gametes are functional. Double fertilisation is a process in which the egg nucleus and secondary nucleus are fertilized at one time by the male gametic nuclei. The fusion of one male gamete nucleus (1n) with egg or oosphere (1n) is called syngamy and results in the formation of oospore (2n). The second male gamete fuses with the secondary nucleus; it is called triple fusion which results in the formation of the primary endosperm nucleus (3n). Thus it takes place in the embryo sac . It was first discovered by Nawaschin (1898).
