Nervous system

• Nervous System - contains a network of specialised cells called neurons that coordinate actions and transmit signals between different body part.
• Central Nervous System (CNS) - The brain and spinal cord.
• Peripheral nervous system (PNS) - All the nerves outside the CNS, including sensory receptors and motor endings.
• Autonomic nervous system (ANS) - Part of PNS which controls involuntary functions such as heart rate, digestion etc.

  Controls internal movement such as endocrine system, glands.
• Somatic nervous system (SNS) - Part of PNS which controls voluntary movements, sensing external stimuli, controls all senses.
• Sympathetic Nervous system - Stimulates the body to prepare for fight or flight

  • dilates pupils
  • secretes adrenaline
  • inhibits salivation
  • dialates bronchi
• Parasympathetic nervous system - stimulates relaxing responses, returns body into normal homeostatic state:

  • slows down heart rate
  • constricts pupils
  • stimulates salivation
  • constricts bronchi
• Autonomic nervous system

  Just motor (movement) - input from internal receptors, output to integral organs, blood vessels
• Somatic nervous system

  Senses + motor (skeletal + muscles)

  Input from sense organs (detect changes), output to muscles, skin and joints (muscles attached to skeleton recieve signals)