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Atlas of Human Embryos Chapter   Figure

C-8 spinal ganglion, T-1 ventral primary ramus, allantois, dorsal aorta, dorsal meso-esophagus, ductus venosus, efferent vein, esophageal endoderm, hepatic sinusoids, left umbilical artery, liver prominence, lower lobar bud, marginal vein, mesonephric artery, mesonephric duct, peritoneal cavity, pleuroperitoneal opening, pneumato-enteric recess, primitive hand plate of upper limb bud, primitive pleural cavity, rib 1 primordium, right hepatocardiac vein, right umbilical artery, septum transversum, umbilical coelom, umbilical cord, umbilical vein

A section through the C-8 spinal ganglion and first rib primordium.

Observe:
1. The primitive hand plate of the upper limb bud with the peripheral marginal vein.
2. The communication of the primitive pleural and peritoneal cavities through the pleuroperitoneal opening ventral to the mesonephric duct.
3. The cranial end of the mesonephric duct.
4. The junctions of an efferent vein and the ductus venosus with the right hepatocardiac vein.
5. The components of the umbilical cord.


Keywords: C-8 spinal ganglion, T-1 ventral primary ramus, allantois, dorsal aorta, dorsal meso-esophagus, ductus venosus, efferent vein, esophageal endoderm, hepatic sinusoids, left umbilical artery, liver prominence, lower lobar bud, marginal vein, mesonephric artery, mesonephric duct, peritoneal cavity, pleuroperitoneal opening, pneumato-enteric recess, primitive hand plate of upper limb bud, primitive pleural cavity, rib 1 primordium, right hepatocardiac vein, right umbilical artery, septum transversum, umbilical coelom, umbilical cord, umbilical vein

Source: Atlas of Human Embryos.