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Atlas of Human Embryos Chapter   Figure

amniotic cavity, ectoderm, endoderm, lateral body fold, mesoderm, primitive groove, primitive streak, umbilical vesicle cavity

A section through the middle part of the primitive streak and groove.

Observe:
1. The thick layers of ectoderm and mesoderm.
2. The thin layer of endoderm that is beginning to enclose the dorsal part of the yolk sac cavity.


Keywords: amniotic cavity, ectoderm, endoderm, lateral body fold, mesoderm, primitive groove, primitive streak, umbilical vesicle cavity

Source: Atlas of Human Embryos.