Biology - Neural Control and Coordination Question with Solution | TestHub

During the generation of an action potential, depolarization is caused by the rapid influx of sodium ions into the axoplasm.

Within a fraction of a second, the sodium channels close and potassium channels open. Potassium ions rapidly diffuse outside the membrane.

This rapid efflux of potassium ions restores the resting potential of the axonal membrane at the site of excitation, making the nerve fibre responsive to further stimulation.

Answer: rapid diffusion of potassium ions to outside of the membrane.