Embryoblast (from Greek έμβρυο , germ ' and βλαστος , shoot' ) is a technical term from the embryology to the part of the blastocyst from which the actual embryo developed.
The embryoblast in mammals (with the exception of the mammals , which have no blastocyst and therefore no embryoblast) can be divided into three cotyledons after gastrulation :
A distinction must be made between the embryoblast and the trophoblast , the part of the blastocyst from which extraembryonic tissue develops, for example the membrane and, in higher mammals , part of the placenta . In humans, the differentiation of embryonic cells into embryoblast and trophoblast takes place around the 4th day of embryonic development .
Embryonic stem cells are obtained from the embryoblast .