habituation

• habituation

  • animals respond to changes in external or internal environments to survive

  1)changes in enviro/stimuli detected by specialised receptor cells

  2)these send signals via nervous/hormonal system to the CNS

  3)CNS sends signals to effectors

  • important animals dont waste energy responding to non threatening stimuli
• • if stimulus is repeated to an animals with no negative outcome, then animals will learn not to respond(habituation)
  • so animal which doesnt respond to a stimulus is habituated to that stimulus
• process of habituation

  • animals become habituated due to changes in transmission of nerve impulses
  • when habituating, fewer CA+ move into the presynaptic neurone so less NT is released and AP less likely to be generated

  1)fewer NT bind to receptors

  2)fewer sodium ion channels open

  3)fewer NA+ move into axon and charge inside neurone remains negative

  4)threshold potential not reached

  • nerve impulse does not reach effector organ and animal does not respond to stimulus