Action Potential

Action Potential

The change of electrical conditions by the passage of an impulse along the membrane of a muscle or nerve cell.
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  1. Resting State- The charge of the cell is -70 mv. The sodium and potassium channels are closed.
  2. Depolarization- The sodium permeability increases, sodium gates open and potassium gates are closed. The charge becomes more positive (-55 to -50 mV)
  3. Repolarization- The sodium gates close while the potassium gates open. Potassium exits the cell and internal negativity is restored, the charge is +30 mV
  4. Hyperpolarization- The potassium gates remain open causing excessive efflux of potassium which causes hyperpolarization, the charge becomes -75 mV 
  5. Na+/K+ pump-  Restores the restating electrical conditions of the neuron

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