Which process returns the membrane to its negative state after depolarization?

Which process returns the membrane to its negative state after depolarization?

• A. Depolarization
• B. Repolarization
• C. Hyperpolarization
• D. Resting potential

Answer: (B)

When the membrane has just depolarized, the next phase that brings it back toward a negative value is repolarization. This happens because voltage‑gated potassium channels open and potassium ions flow out of the cell. The outward movement of positive charge makes the inside more negative, restoring the membrane potential toward its resting (negative) state. Sometimes the outflow overshoots a bit, causing a brief hyperpolarization below resting potential, but the resting level is ultimately reestablished by leak channels and the Na+/K+ pump. So the process that returns the membrane to its negative state after depolarization is repolarization.

When the membrane has just depolarized, the next phase that brings it back toward a negative value is repolarization. This happens because voltage‑gated potassium channels open and potassium ions flow out of the cell. The outward movement of positive charge makes the inside more negative, restoring the membrane potential toward its resting (negative) state. Sometimes the outflow overshoots a bit, causing a brief hyperpolarization below resting potential, but the resting level is ultimately reestablished by leak channels and the Na+/K+ pump. So the process that returns the membrane to its negative state after depolarization is repolarization.