Question

What does 4-nucleated, 8-nucleated embryo sac mean in the sexual reproduction of plants?

Answer 1

Embryo sac is the female gametophyte of a seed plant consisting of a thin-walled sac within the ovule that contains the egg nucleus and other nuclei which give rise to endosperm on fertilization.

The type of embryo sac development depends on the number of spore nuclei entering into it.

In the monosporic, meiosis of diploid mother cell produces four haploid megastore, three of which undergo programmed cell death. In bisporic, meiosis produces only two megaspore s each containing two haploid nuclei one of which dies. In the tetrasporic cell, plate fail to form after both meiosis divisions resulting in a single four nuclear megaspore

All megaspore can develop in eight nuclear embryo sac.