PATHOLOGY

Detailed explanation-1: -Depolarization is caused when positively charged sodium ions rush into a neuron with the opening of voltage-gated sodium channels . Repolarization is caused by the closing of sodium ion channels and the opening of potassium ion channels.

Detailed explanation-2: -The neuron cell membrane is partially permeable to sodium ions, so sodium atoms slowly leak into the neuron through sodium leakage channels. The cell wants to maintain a negative resting membrane potential, so it has a pump that pumps potassium back into the cell and pumps sodium out of the cell at the same time.