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What Is the Nervous System?
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The spinal cord transmits messages to the brain where they are analyzed and
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Hi, I'm Jim Shields for About.com, and today I'm going to teach you about the nervous system.  The nervous system controls all the functions of the body by both giving instructions and carrying out communication between body parts. The basic units of the nervous system are neurons, which are specialized cells that transmit information.A neuron is a cell with two important parts that send and receive messages in the form of electrical impulses. The axon is a projection from the cell body of the neuron that transmits signals away from the neuron, while dendrites receive signals from other neurons. This is how information is sent around the nervous system throughout the body.  The nervous system is comprised of the brain, spinal cord, nerves, and sense organs like the eyes, ears, nose, mouth and skin. It is divided into two parts: the central nervous system and the peripheral nervous system. In the central nervous system, the spinal cord transmits messages to the brain, where they are analyzed and interpreted. The brain sends response messages back through the spinal cord to the rest of the body.    The peripheral nervous system, is made up of all the neurons that are not part of the brain or spinal cord. Some of the neurons in the peripheral nervous system are responsible for collecting information from the body and transmitting it toward the central nervous system, while other neurons are responsible for sending messages away from the central nervous system to the various parts of the body. So remember, the central nervous system, made up of the brain and the spinal cord, and the peripheral nervous system, made up of all the neurons not in the brain and spinal cord, work together to communicate with and give instructions to the body. Thanks for watching. To learn more about biology, visit us on the web at About.com.
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