Neurones

• Sensory neurones carry electrical impulses from receptors to the central nervous system (CNS).
• Relay neurones are found in the CNS and carry impulses from sensory neurones to motor neurones.
• Motor neurones carry impulses from the CNS to effectors, like muscles and glands.
• Sensory neurones have:

  • Axon: carry impulses long distances
  • Fatty myelin sheath: insulates the neurone
  • Gaps between each myelin sheath: speed up rate of transmission
  • Axon terminals: pass impulses to other neurones
  • Dendrites: collect impulses from receptor cells
• Relay neurones have:

  • Dendrites: collect impulses from sensory neurones
  • Cell body
  • Axon: carry impulses long distances
  • Axon terminals: pass impulses to other neurones
• Motor neurones have:

  • Dendrites: collect impulses from relay neurones
  • Cell body
  • Can have myelin sheath or not
  • Axon: carry impulses long distances
• All neurones have axons, myelin sheath and cell body