Cards (6)

  •  The nervous system enables humans to react to their surroundings and
    coordinate their behaviour.
  • Information from receptors passes to the central nervous system
    (CNS) (the brain and spinal cord).
  • The CNS coordinates the response of effectors, i.e. muscles
    contracting or glands secreting hormones.
  •  Reflex actions are automatic and rapid so they can protect the body.They do not involve the conscious part of the brain:
    1. The pain stimulus is detected by receptors.
    2. Impulses from the receptor pass along a sensory neurone to the
    CNS.
    3. An impulse then passes through a relay neurone.
    4. A motor neurone carries an impulse to the effector.
    5. The effector (usually a muscle) responds, e.g. to withdraw a limb
    away from the source of pain.
  • . Neurones are not directly connected to each other.
  • . They communicate with each other via synapses (gaps between
    neurones).