What happens to K+ ions during repolarization of a neuron?

During repolarization of a neuron, the membrane potential of the neuron returns to a more negative value after depolarization. This process primarily involves the movement of potassium ions (K+) across the neuron's membrane. As the neuron depolarizes due to the influx of sodium ions (Na+) during an action potential, K+ channels open in response to this change in voltage.

As these potassium channels open, K+ ions flow out of the cell, taking positive charge with them. This efflux of K+ ions is crucial, as it helps restore the resting membrane potential by counteracting the previous influx of Na+ ions. The outward movement of K+ contributes to the repolarization phase, leading the neuron back to its resting state.

Therefore, the correct understanding is that during repolarization, K+ ions leave the cell, which is essential for the restoration of the neuron's resting potential following an action potential.