SPINAL NERVE

in vertebrates, any one of many paired nerves that leave the spinal cord at regular intervals. Each pair connects the spinal cord with a specific region of the body. Near the spinal cord each spinal nerve branches into two roots. One, with fibres of sensory nerve cells (neurons), enters the spinal cord via the dorsal root; its cell bodies lie in a spinal ganglion that is outside the spinal cord. The other, with fibres of motor neurons, leaves the spinal cord via the ventral root; its cell bodies lie in specific areas of the spinal cord itself.