How does an action potential propagate?
a stimulus depolarises the membrane potential above the threshold level e.g. -40 mvthis causes voltage gated Na+ ion channels to open- resulting in an influx of Na+ into the cellthis depolarises the membrane to +40 mvthen voltage gated K+ ion channels open resulting in an efflux of K+ out of the cell- this hyper polarises the cellthe Na-K pump restores the membrane potential
SA
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