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Atlas of Human Embryos Chapter   Figure

amniotic duct, connecting stalk, embryonic ectoderm, embryonic endoderm, embryonic mesoderm, primitive groove, primitive streak

A section through the middle of the primitive streak.

Observe:
1. The slight depression in the ectoderm forming the primitive groove over the streak area.
2. The cut edge of the connecting stalk that attaches the embryo to the inner aspect of the chorion.
3. The amniotic duct extending into the stalk.


Keywords: amniotic duct, connecting stalk, embryonic ectoderm, embryonic endoderm, embryonic mesoderm, primitive groove, primitive streak

Source: Atlas of Human Embryos.