Nerve impulses

• The electrical impulse that passes along an axon is an electrical potential due to differences in charge

  • this is because of the distribution of Na+ and K+ either side of the axon membrane
• Label this graph of a nerve impulse transmission

  A) Resting potential

  B) -70mV

  C) Threshold

  D) -55mV

  E) Na+ channels open

  F) Depolarisation

  G) Na+ channels close

  H) +40mV

  I) Action potential

  J) K+ channels open

  K) Repolarisation

  L) Refractory period

  M) Hyperpolarisation

  N) K+ channels close

  O) Resting potential