Brief notes on spinal nerves.

Explanation

Spinal nerves 31 pairs of spinal nerves emcrge out from the spinal cord through spaces called the intervetcbral foramina found between the adjacent vertebrac. The spinal nerves an named according to the region of vertebral column from which they originate
i. Cervical nerves (8 pairs)
ii. Thoracic nerves (12 pairs)
iii. Lumbar nerves (5 pairs)
iv. Sacral nerves (5 pairs)
v. Coccygeal nerves (1 pair)
Each spinal nerve is a mixed containing both afferent (sen sory) and efferent (motor) fibers. It originates as two root 1) a posterior doral root with a ganglion outside the spinal cord and 2) an anterior ventral root with no external ganglion.