The Brain
The human brain is the remarkable master control center of all processes that keeps the human body systems running efficiently twenty four hours a day. It is the center of our conscious processes like thinking, daydreaming, and learning. It is the largest and most complex part of the nervous system. It receives information, process information, and responds appropriately to information. A brain holds 1000 times more information than a twenty volume encyclopedia (Oleksy, 2001). The brain is a soft, grayish pink, jellylike organ that weighs about three pounds, 2% of the body’s weight, is about the size of a grapefruit and is 80% water.
It uses up nearly one
fifth of the body’s vital oxygen supply and glucose, high energy sugar found in
the blood. The brain uses ten times more glucose and oxygen than most other
body parts. The brain receives twenty four ounces of blood each minute. The brain contains over 100 billion neurons and 900 billion supportive neuroglia. The brain is formed during fetal development as neurons are formed and divide. This process continues until infants are a few months old. At that point no new brain cells are formed but the present neurons continue to grow until age eighteen (Walker, P. & Wood, E., 2003).
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