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Atlas of Human Embryos Chapter   Figure

S-1 somite, T-6 dermatome, T-6 neural crest, alar plate, basal plate, cloaca urogenital sinus portion and rectal portion, dorsal mesentery, epithelioid cells, floor plate, gonadal ridge, hindgut, left umbilical artery, left umbilical plexus, lower limb bud: placode and mesoderm, mesonephric duct, mesonephric vesicle, myocoele, neural canal, notochord, right umbilical artery, right umbilical vein, roof plate, sclerotome, sulcus limitans

A section through the T-6 neural crest, S-1 somite and the cloaca.

Observe:
1. The mycocoele of the S-1 somite surrounded by epitheloid cells.
2. The urogenital sinus and rectal portions of the cloaca.
3. The distal part of the lower limb buds with its ectodermal placode and mesodermal core.
4. The caudal extent of the left umbilical plexus in the lateral body wall.
5. The midsection of a mesonephric vesicle.


Keywords: S-1 somite, T-6 dermatome, T-6 neural crest, alar plate, basal plate, cloaca urogenital sinus portion and rectal portion, dorsal mesentery, epithelioid cells, floor plate, gonadal ridge, hindgut, left umbilical artery, left umbilical plexus, lower limb bud: placode and mesoderm, mesonephric duct, mesonephric vesicle, myocoele, neural canal, notochord, right umbilical artery, right umbilical vein, roof plate, sclerotome, sulcus limitans

Source: Atlas of Human Embryos.