The Nervous System

• The two divisions of the Nervous System

  The Central Nervous System and The Peripheral Nervous System
• Parts of the CNS

  Brain and Spinal Cord
• Two divisions of PNS

  Autonomic NS and the Somatic NS
• Divisions of the Autonomic NS

  Sympathetic and the Para-Sympathetic
• Role of the PNS

  relays messages from the environment to the CNS via sensory neurones, and from the CNS to effectors via motor neurones
• Role of autonomic NS


  controls involuntary, vital functions of the body
• Examples of functions that the ANS controls

  maintaining heart rate and breathing rates
• Role of the somatic NS

  voluntary movement and the reception of external stimuli
• Examples of functions of the SNS

  Muscle contractions
• Sympathetic NS - Fight or flight

  • heart rate increases
  • Breathing rate increases
  • vasoconstriction
  • pupil dilation
• Parasympathetic - rest or digest

  • decreases hr
  • decrease breathing rate
  • vasodilation
  • pupil constriction