What returns a neuron to its resting potential after it has depolarized?

1. Depolarization itself causes the membrane to become impermeable to sodium again. 2. Potassium then moves from high concentration to low, which means outward. 3. That movement quickly restores the resting potential, and the cell is said to repolarize. 4. Depolarization followed by repolarization gives the voltage pulse called the action potential. 5. Sodium moving inward is the depolarizing step, so choosing it reverses the sequence. _Source: OpenStax College Physics (CC BY 4.0), Ch 20 "Electric Current, Resistance, and Ohm's Law", section Nerve Conduction_