31 pairs
Spinal nerve, in vertebrates, any one of many paired peripheral nerves that arise from the spinal cord. In humans there are 31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each pair connects the spinal cord with a specific region of the body.
Development is where the growth of the embryo occurs. After fertilization and implantation, the growth of the embryo occurs once it gets to the uterus. This is the part where the procedure where the embryo turns into a living being over time - depending on the animal that has the said embryo.
