The Nervous system

• Central Nervous System (CNS):

  • Brain - centre of all conscious awareness
  • Spinal Chord - an extension of the brain responsible for reflex actions
• Peripheral Nervous System (PNS)

  • Somatic NS - controls muscle movement and receives information from sensory receptors
  • Autonomic NS - governs vital functions in the body such as breathing, heart rate, digestion
• Role of CNS - passes messages to and from the brain and connects nerves to the PNS
• Role of PNS - transmits messages, via neutrons, to and from the CNS
• Autonomic Nervous System (ANS)

  • Sympathetic division - speeds up alertness and response time
  • Parasympathetic division - slows down transmission
• Role of Sympathetic division - speeds things up, involved in fight or flight and processes that help us in emergencies (neurotransmitter - Noradrenalin)
• Effects of Sympathetic division

  • increased blood pressure and arousal
  • accelerated heart rate
  • dilates pupils
• Role of Parasympathetic division - works to calm the body down after arousal to its normal 'resting' functions (neurotransmitter - Acetylcholine)
• Effects of Parasympathetic division

  • constricts pupils
  • slows heart rate
  • lowers blood pressure