Describe the sequence of events during an action potential, including ion movements and key voltage-gated channels.

• A. Resting potential; depolarization via Na+ influx through voltage-gated Na+ channels; reach threshold; peak; repolarization via K+ efflux through voltage-gated K+ channels; hyperpolarization; Na+/K+ ATPase restores resting potential.
• B. Action potential begins with Cl- influx; hyperpolarization first then depolarization.
• C. Depolarization occurs via Ca2+ influx; repolarization via Na+ influx.
• D. Resting potential; depolarization via K+ efflux; repolarization via Na+ influx.

Answer: (A)