Characteristic Features of Avian Gastrulation
- Creation of hypoblast and its important role in formation of the axis and orientation of embryo.
- Existence of the cells of all the three germinal areas in the epiblast.
- Creation of the primitive streak and its regression in law stages of gastrulation.
- Nonexistence of archenteron formation.
- Gastrula cell movements include poly invagination, involution, convergence, divergence and epiboly.
- Cephalocaudal separation of axial structures and growth of the embryo during gastrulation.