Description of embryonic sac

Question

Give a brief description of the term embryonic sac? Which are the cells that form embryonic sac? And also write down their ploidies?

Answer 1

The embryonic sac is female gametophyte of the angiosperms. The embryonic sac is composed of three cells which remain next to micropyle, two lateral synergids and central oosphere (egg); one binucleated cell, polar nuclei, is placed in central region; three antipodal cells stay in opposite side to micropyle.

Because all of these cells come by the mitosis from functional megaspore they are haploid.