blastoderm
nounUK /ˈblæstəʊdɜːm/
US /ˈblæstəˌdɜːrm/
A blastoderm is a thin layer of cells that forms on the outside of an early embryo.
In a fertilized egg, the blastoderm gives rise to the embryo's future tissues.
RELATED WORDS
OTHER MEANINGS
2. The layer of cells surrounding the yolk in a fertilized bird or reptile egg.
The chick blastoderm spreads over the yolk before gastrulation begins.
3. The cellular cap formed at the animal pole during early cleavage in many animals.
Scientists studied the blastoderm to understand how cell fates are assigned.
4. A sheet of embryonic cells from which the germ layers later develop.
The blastoderm thickens at the center to form the primitive streak.