The brain and The main nerve trunk running down the spinal canal and connecting the individual’s mind and consciousness to the rest of his or her body. It is about the size of a person’s little finger, in diameter. It cannot repair itself if damaged. together make up the central nervous system. Nerves issue from both structures, passing out of the head and The individual bones that comprise the spinal column are made up of a weight-bearing “body” and other components which, together, form a ring of bone, behind the body. These individual vertebrae, joined together as the spinal column, therefore, create a canal running down the entire length of the spine., to supply all parts of the body, thereby allowing for voluntary movements to take place, various senses to be perceived and for the function of many internal organs to be regulated. Collectively, these nerves make up the From the Greek and meaning “around”, or away from the centre, this word refers to those parts of the nervous system that lie outside the head and spine or, more accurately, outside the brain and the spinal cord. Together they constitute the peripheral nervous system, which itself is made up of sensory nerves, nerves controlling motor functions and autonomic components. nervous system.