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Atlas of Human Embryos Chapter   Figure

amniotic cavity, ectoderm, embryonic disc, endoderm, junction of mesoderm and endoderm, mesoderm, prechordal plate, primordial pericardial cavity

A section through the cranial part of the embryonic disc showing the prochordal plate.

Observe:
1. The broader embryonic disc with the primary germ layers having characteristics similar to those in Section 1.
2. Another junction region between mesodermal and endodermal cells.
3. Thickened, midline endoderm forming the prochordal plate.
4. Small spaces in the mesoderm at the edge of the disc that will form the pericardial cavity.


Keywords: amniotic cavity, ectoderm, embryonic disc, endoderm, junction of mesoderm and endoderm, mesoderm, prechordal plate, primordial pericardial cavity

Source: Atlas of Human Embryos.