Blastocyste

Etymology

Comes from the Greek: of βλαστός (germ, bud) and κύστις (bladder)

Definition

The blastocyste , or blastula , is a stage of the early development Embryon naire of the Mammifères (from 5 to 6 days at the man) during which the peripheral cells coexist, called cells of the trophectoderme, at the origin of the Placenta, and the cells of the internal mass, which form the embryonic button and give rise to the embryo itself and to some additional embryonic. The blastocyste is resulting from the Blastulation of the Morula (16 identical cells), and comprises a hundred cells constituting the internal mass at the sixth day.

The cells of the internal mass can be taken and cultivated in vitro: they are the embryonic original cells (cells ES). Cultivated in an adequate way, they can maintain to them Pluripotence and thus generate at the time of their Différenciation any cellular type (including the germinal cells).

Not to confuse

blastocyste, subst. masc. “The segmented Shape of fertilized egg when it penetrates in the uterine Muqueuse ”
Blastocyte, subst. masc. “Not yet differentiated Embryonic cell”

Random links: