What do you understand by peripheral nervous system ?
A. 1) The peripheral nervous system consists of nerves that arise from the brain and spinal cord.
2) The peripheral nervous system has 43 pairs of nerves of these 12 pairs are called CRANIAL NERVES and the rest of 31 pairs are called SPINAL NERVES.
3) The grey matter of the spinal cord appears like butterfly or in the shape of letter ‘H’. Each segment of the ‘H’ shaped grey matter is called ‘HORNS’.
4) The upper horns are called 'DORSAL HORNS’ and the lower horns are called ‘VENTRAL HORNS’.
5) The sensory fibres originate from the dorsal horn of the spinal cord; They carry information from body organs to spinal cord.
6) The motor, fibres take their origin from the ventral horns of the spinal cord. These
supply information required for the movements of the muscles.