B10: The Human Nervous System


B10.1: Principles of Homeostasis

  • homeostasis is the regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes.
  • homeostasis is important for maintaining optimal conditions for enzyme action and all cell functions. 
  • in the human body homeostasis includes the control of blood glucose concentration, body temperature and water levels. 
  • the automatic control systems may involve nervous or chemical responses.
  • all control systems include receptor, co-ordination centres and effectors. 
1 of 3

B10.2: The Structure and Function of the Human Ner

  • the nervous sytem uses electrical impulses to enable you to react quickly to your surroundings and coordinate your behaviour.
  • cells called receptors detect stimuli.
  • impulses from receptors pass along sensory neurones to the brain or spinal cord (CNS).
  • the brain coordinates the response and impulses are sent along motor neurones from the brain to the effectors. 
2 of 3

B10.3: Reflex Actions

  • reflex actions are automatic and rapid and don't involve the concious parts of the brain.
  • reflexes involve sensory, relay and motor neurones. 
  • reflex actions control everyday bodily functions and to keep you out of danger.
  • the reflex arc:
    • stimulus
    • receptor
    • sensory neurone
    • relay neurone
    • motor neurone
    • effector
    • response
3 of 3


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Homeostasis resources »