Draw a labelled diagram of a m.ature embryo sac
Why does a pollen grain possess two male gametes? Explain.

Explanation

A diagrammatic representation of the mature embryo sac.
Pollen grains possess two male gametes as it is required for double fertilization in most angiosperms. Out of two male gametes, one male gamete moves towards egg cell and fuses with · its nucleus to form a diploid cell called zygote and another male gamete fuses with two polar nuclei (secondary nuclei if they. are already fused) to produce a triploid primary endosperm nucleus (PEN).