In terms of its anatomical structure, the nervous system is usually considered to have two distinct parts:

• the central nervous system (commonly abbreviated to CNS ), which consists of the brain and the spinal cord, and
• the peripheral nervous system, which is made up of nerves that extend from the central nervous system to all parts of the body. There are 12 pairs of cranial nerves and 31 pairs of spinal nerves.




Click PLAY to compare the central nervous system and peripheral nervous systems.