THE NERVOUS SYSTEM

Information is passed through the body rapidly through specialised cells (nerve cells or neurons). These transmit information as an electrical impulse.

Nerves are arranged in the body in the :

Central Nervous System (CNS) - regulation and control - includes the brain and spinal cord

Peripheral Nervous System - transmission of information

There are three sorts of neurons :

    Sensory Neurons - receptors

    Interneurons - transmit information

    Effector Neurons - stimulate organs which generate a response

Information is transmitted between neurons across a tiny gap called a synapse. Neurotransmitters are chemicals which carry the nerve impulse across the synapse.

Control in the body is maintained by negative feedback systems, where the response generated serves to lessen the original stimulus.




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© 2004 Dr Peter Darben