In angiosperm : 1. After pollination, the pollen grains germinate on the stigma and the resulting pollen tubes grow through the tissues of stigma and style and reach the ovule. 2. The pollen tubes enter the embryo-sac where two male gametes are discharged. 3. One of the male gametes fuses with the egg cell to form a zygote (syngamy). 4. The other male gamete fuses with the diploid secondary nucleus to produce the triploid primary endosperm nucleus (PEN). 5. This event is termed as double fertilisation Regarding 1,2,3,4 and 5:
