Noun: gastrula (gastrulae) gas-trû-lu
- Double-walled stage of the embryo resulting from invagination of the blastula; the outer layer of cells is the ectoderm and the inner layer differentiates into the mesoderm and endoderm
"The gastrula stage marked the beginning of organ development"
Derived forms: gastrulae
Type of: conceptus, embryo, fertilised egg [Brit], fertilized egg
Encyclopedia: Gastrula