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Atlas of Human Embryos Chapter   Figure

cloacal membrane, ectoderm, endoderm, hindgut, neural fold, neural groove, notochord, paraxial mesoderm, tail fold region, vitelline plexus

A section through the embryo caudal to the tail fold at the level of the cloacal membrane.

Observe:
1. The embryo completely clothed in ectoderm.
2. The fusion of endoderm and ectoderm at the cloacal membrane in the floor of the hindgut.
3. The thick, solid layer of mesoderm.
4. The caudal end of the notochord where it has a rounded appearance on cross section.
5. The neural folds and groove.


Keywords: cloacal membrane, ectoderm, endoderm, hindgut, neural fold, neural groove, notochord, paraxial mesoderm, tail fold region, vitelline plexus

Source: Atlas of Human Embryos.