Question

Write a short note on embryo sac.

Answer 1

1. The embryo sac is a multicellular oval structure implanted within the nucleus.
2.  The egg apparatus is a three-celled structure located at the embryo sac's micropylar end. It is made up of an oosphere, a median egg cell, and two synergids, which are lateral cells.
3.  The embryo sac also contains three antipodal cells or antipodals that disintegrate following fertilisation.
4. The embryo sac contains a big core cell with two haploid polar nuclei in the centre.
5. At a later stage, the polar nuclei combine, generating a diploid secondary nucleus. After fertilisation, the secondary nucleus develops into an endosperm.