Final answer:
Hyperpolarization is caused by delayed closing of K+ channels. When a cell is depolarized, voltage-gated Na+ channels open and allow sodium ions to enter the cell. Subsequently, voltage-gated K+ channels open and potassium ions leave the cell, which helps repolarize the membrane potential.
Step-by-step explanation:
Hyperpolarization is caused by the delayed closing of K+ channels. When a cell is depolarized, voltage-gated Na+ channels open and allow sodium ions to enter the cell. Subsequently, voltage-gated K+ channels open and potassium ions leave the cell, which helps repolarize the membrane potential. However, these potassium channels do not close immediately once the membrane potential reaches its resting state, resulting in a hyperpolarizing overshoot.