Nerve injury from a head injury, spinal cord injury, or neurological disease processes varies by the type of injury to nerves. The injury can occur in various aspects of the nerve and nerve transmission. Diseases or trauma may affect nerves differently.
The basic construction of a nerve has been identified and mapped out. A single nerve in the body consists of nerve fibers that are packaged together in bundles. Several nerve bundles are in every nerve. The outside layer of the nerve is covered in protein and fatty substances called myelin. This insulation of the nerve keeps messages (nerve impulses) flowing smoothly.
Nerves consist of three main parts: dendrites, a body, and an axon with an axon terminal. The cell body is a structure with a nucleus in the center of the body and short dendrites extending out of the body. It looks like a microscopic fried egg with branches coming off the edges. This is the powerhouse of the nerve. The cell body controls all the functions of the nerve.
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