These layers, similar to tubing, are the dura mater, or simply the 'dura', the arachnoid, and the pia mater. The fluid acts as a defensive cushion that protects the spinal cord, which is an organ central to the operation of the nervous system. Between each vertebra, on both the left and right sides, a window is formed termed the neuroforamen. The nerve roots slip through these windows and spread into the body like tree branches. Not only do thousands of nerves send and receive signals from the brain to interior structures, but special nerves connect to the skin.
Dermatomes are specific areas of skin controlled by nerve endings.
In Latin, derma denotes 'skin' and tome refers to 'a section'. This site uses Flash media extensively.