An action potential involves Na+ influx causing depolarization, followed by Na+ channel closure and K+ efflux causing repolarization and hyperpolarization; the Na+/K+ ATPase then re-establishes the resting potential.
- energy from stimulus opens Na+ channels - Na+ diffuses in - depolarisation opens more voltage gated Na+ channels - more Na+ diffuses in - membrane potential reaches +40mV - voltage gated Na+ channels close - voltage gated K+ channels open - K+ diffuse out - repolarisation - hyperpolarisation - -80mV - voltage gated K+ channels close - Na+ K+ ATPase actively transports 3 Na+ out and 2 K+ in - resting potential -70mV reestablished
| Front | Describe the action potential. |
|---|---|
| Back | - energy from stimulus opens Na+ channels - Na+ diffuses in - depolarisation opens more voltage gated Na+ channels - more Na+ diffuses in - membrane potential reaches +40mV - voltage gated Na+ channels close - voltage gated K+ channels open - K+ diffuse out - repolarisation - hyperpolarisation - -80mV - voltage gated K+ channels close - Na+ K+ ATPase actively transports 3 Na+ out and 2 K+ in - resting potential -70mV reestablished |
Tags: nerves
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