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Atlas of Human Embryos Chapter   Figure

L-1 spinal nerve, L-2 spinal nerve, L-3 sclerotome: rostral part (vertebra) and caudal part (intervertebral disc), L-3 spinal nerve, L-4 body segment, L-4 myotome, L-4 spinal nerve, L-5 spinal nerve, S-1 spinal nerve, S-2 spinal ganglion, T-12 spinal ganglion, dermatome cells, dermatome remnant, dorsal intersegmental arteries, ectoderm, gluteal mesoderm, notochord, primitive meninx

A section through the T-12 and S-2 spinal ganglia.

Observe:
1. The sclerotomes with their loose rostral and dense caudal parts.
2. The notochord in longitudinal section.
3. The intersegmental position of the dorsal intersegmental arteries.
4. The segmental position of the spinal nerves and myotomes.
5. The dermatome cells between the ectoderm and the myotome.


Keywords: L-1 spinal nerve, L-2 spinal nerve, L-3 sclerotome: rostral part (vertebra) and caudal part (intervertebral disc), L-3 spinal nerve, L-4 body segment, L-4 myotome, L-4 spinal nerve, L-5 spinal nerve, S-1 spinal nerve, S-2 spinal ganglion, T-12 spinal ganglion, dermatome cells, dermatome remnant, dorsal intersegmental arteries, ectoderm, gluteal mesoderm, notochord, primitive meninx

Source: Atlas of Human Embryos.