Embryo sac refers to the female gametophyte in an angiosperm.
The embryo sac is found within the nucellus and integuments of the ovule or the megasporangium.
In most angiosperms, a single megaspore produces a female gametophyte.
Megasporogenesis is the process of the formation of megaspores.
The diploid megaspore mother cell divides into four megaspores during meiosis.
Only one functioning cell contributes to the development of the embryo sac after the degeneration of three cells and this type of embryo sac is known as a monosporic embryo sac.
This type of embryo sac development is known as monosporic development.