Parts of The Blastocyst
The blastocyst consists of two primary cell types:
- the inner cell mass, also known as the "embryoblast" (this part of the embryo is used in stem cell research)
- the trophoblast, a layer of cells surrounding the inner cell mass and the blastocyst cavity (blastocoele).
The former is the source of embryonic stem cells and gives rise to all later structures of the adult organism. The latter combines with the maternal endometrium to form the placenta in eutherian mammals.
Read more about this topic: Blastocyst
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