CNS ( Central Nervous System)
The nervous system, the entire nervous apparatus of the body. It
controls all muscular movements, both voluntary and involuntary; is closely
connected with thought processes; regulates such body functions as circulation,
respiration, digestion, and elimination; and conducts pain and other sensations
to the brain. The central nervous system, comprising the brain and spinal cord; and the
peripheral nervous system which consists of the twelve pairs of cranial nerves
arising from the brain, three pairs of nerves coming from the spinal cord, and
the nerves of the sympathetic (autonomic) nervous system which supply the
internal organs and blood vessels. Nerve cells with their fibers are the units
of the nervous system. The operation of the nervous system depends in these
nerve cells (gray matter) and their nerve fibers (white matter). The function
of the white matter is to conduct these impulses to and from the cells in the
gray matter. Nerve tissue itself consists of the cells with nuclei and
threadlike axons which conduct impulses from the nerve cells. Most nerve cells
also relatively short processes called dendrites which conduct impulses into the
cell. Impulses normally flow in one direction only. In the afferent nerve they
flow toward the cell and in the efferent nerve they flow away from the cell. A
nerve cell with its axon and dendrite is called a neuron and the entire structure
of the nervous systems is made up of a relay of neurons. A nerve consists of
bundles of nerve fibers and is supplied with blood vessels, lymphatics, and
other nerves. Some nerves are afferent, some are efferent, and others are mixed.
This picture above is a normal nerve cell found inside the human body and is labeled accordingly.
White and gray matter of the spinal cord.
Pub Med Article relating to the nervous system.
http://www.ncbi.nlm.nih.gov/pubmed/24137362
Citations:Fishbein, Morris. The New Illustrated Medical and Health Encyclopedia.
New York: H. S. Stuttman, 1970. Print.
New York: H. S. Stuttman, 1970. Print.