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Nervous system

Functions of the nervous system

The nervous system performs three functions:

  • sensation - it analyses sensory information from the external environment or the body itself
  • integration - some information is stored and decisions are made about responses to sensory information
  • response - motor responses are brought about, initiating muscular contractions or secretions from glands

Parts of the nervous system

The human nervous system consists of:

  • central nervous system (CNS) 鈥 the brain and spinal cord
  • peripheral nervous system 鈥 nerve cells that carry information to or from the CNS
A diagram of a human body showing the central and peripheral nervous systems

The peripheral nervous system can be further split into two parts:

  • somatic nervous system (SNS) - responsible for concious perception and voluntary movement of skeletal muscles
  • autonomic nervous systems (ANS) - responsible for involuntary control of the body, including glandular secretions, maintaining organ systems and reflex movement of skeletal muscles
Flow chart showing the peripheral nervous system divided into the somatic and autonomic nervous system.