The Blastocyst is the structure formed in early mammalian embryogenesis, after the formation of the blastocele, but before implantation. It possesses an inner cell mass, or embryoblast, and an outer cell mass, or trophoblast.

See also

• Blastula
• Inner cell mass

The blastocyst is formed of pluri-potent cells and go on to form the developing embryo. The outside layer of cells of the blastocyst goes on to form the placenta, and the inner ball of cells forms the embyro.

External links

• Photo
• Blastocyst photos at different stages of development
• Diagram at princeton.edu
• Diagram at weber.edu

Embryology