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Atlas of Human Embryos Chapter   Figure

cephalic end of notochord, cephalic part of foregut, ectoderm, endoderm, head fold region, internal carotid artery, junction of aortic arch 1 and dorsal aorta, mesoderm, neural fold, neural groove, neural plate, oropharyngeal membrane, placode 5, rhombencephalon (preotic), right dorsal aorta, trigeminal neural crest (CN V)

A section through the cranial end of the foregut showing its separation from the exterior by the two-layered, oropharyngeal membrane.

Observe:
1. The preotic part of the rhombencephalon that is open dorsally showing the neural plate, groove and folds.
2. The caudal part of the trigeminal crest extending laterally toward a slightly thickened area of ectoderm (placode V).
3. The cranial end of the foregut lined with endoderm.
4. The cranial ends of the dorsal aortas.
5. The cranial end of the notochord in the roof of the foregut.


Keywords: cephalic end of notochord, cephalic part of foregut, ectoderm, endoderm, head fold region, internal carotid artery, junction of aortic arch 1 and dorsal aorta, mesoderm, neural fold, neural groove, neural plate, oropharyngeal membrane, placode 5, rhombencephalon (preotic), right dorsal aorta, trigeminal neural crest (CN V)

Source: Atlas of Human Embryos.