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Atlas of Human Embryos Chapter   Figure

alar plate(s), aortic arch 3, aortic arch 4, basal plate, closing membrane, dorsal aorta, dorsal thalamus, ectoderm, edge of C-1 neural crest, edge of hypophyseal pouch, edge of hypothalamus, endoderm, floor plate, hypopharyngeal eminence of tongue, internal carotid artery, mesoderm, occipital dermatome, occipital myotome, occipital sclerotome, oropharyngeal junction, pharyngeal arch 1, pharyngeal arch 2, pharyngeal arch 3, pharyngeal groove 1, placode 9-10, precardinal vein, pretectum, primitive pharynx, prosencephalon (diencephalic part), roof plate, sulcus limitans, sulcus medius, vagal preganglion (CN X), ventral thalamus

A section through the cranial edge of the C-1 neural crest and the floor of the primitive pharynx.

Observe:
1. The edge of the hypothalamus and its relation to the hypophyseal pouch and internal carotid arteries.
2. Branchial arches 1 through 4 with closing membranes separating pouches from grooves.
3. The hypobranchial eminence in the midline in the floor of the primitive pharynx (tongue region).
4. The close association of the vagal preganglion with placode IX-X.
5. The junction of aortic arch 4 with the dorsal aorta and its close association to the primitive pharynx.


Keywords: alar plate(s), aortic arch 3, aortic arch 4, basal plate, closing membrane, dorsal aorta, dorsal thalamus, ectoderm, edge of C-1 neural crest, edge of hypophyseal pouch, edge of hypothalamus, endoderm, floor plate, hypopharyngeal eminence of tongue, internal carotid artery, mesoderm, occipital dermatome, occipital myotome, occipital sclerotome, oropharyngeal junction, pharyngeal arch 1, pharyngeal arch 2, pharyngeal arch 3, pharyngeal groove 1, placode 9-10, precardinal vein, pretectum, primitive pharynx, prosencephalon (diencephalic part), roof plate, sulcus limitans, sulcus medius, vagal preganglion (CN X), ventral thalamus

Source: Atlas of Human Embryos.