The brain communicates with the rest of the body through the spinal cord and the nerves. They tell the brain what is going on in the body at all times. This system also gives instructions to all parts of the body about what to do and when to do it.
Nerves divide many times as they leave the spinal cord so that they may reach all parts of the body. The thickest nerve is 1 inch thick and the thinnest is thinner than a human hair. Each nerve is a bundle of hundreds or thousands of neurons (nerve cells). The spinal cord runs down a tunnel of holes in your backbone or spine. The bones protect it from damage. The cord is a thick bundle of nerves, connecting your brain to the rest of your