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Atlas of Human Embryos Chapter   Figure

S-1 spinal ganglion, S-2 spinal ganglion, S-3 ventral primary ramus, S-4 ventral primary ramus, S-5 ventral primary ramus, centrum, coccygeal ventral primary ramus, digit 5, edge of buttock, intervertebral disc, left umbilical artery, neural canal, notochord, primitive filum terminale, right umbilical artery, tail bud remnant, umbilical coelom, umbilical vein, vitelline (omphalomesenteric) artery, vitelline (omphalomesenteric) vein

A section through the S-2 spinal ganglion and the ventral primary rami of remaining spinal nerves (S-3 through coccygeal).

Observe:
1. The primitive filum terminale ending in the tail bud remnant where the coccyx will form.
2. The notochord in longitudinal section.
3. The centrum and intervertebral disc of the vertebral column.
4. The primordium of the fifth digit of the foot.


Keywords: S-1 spinal ganglion, S-2 spinal ganglion, S-3 ventral primary ramus, S-4 ventral primary ramus, S-5 ventral primary ramus, centrum, coccygeal ventral primary ramus, digit 5, edge of buttock, intervertebral disc, left umbilical artery, neural canal, notochord, primitive filum terminale, right umbilical artery, tail bud remnant, umbilical coelom, umbilical vein, vitelline (omphalomesenteric) artery, vitelline (omphalomesenteric) vein

Source: Atlas of Human Embryos.