Final answer:
Hyperpolarization is a change in the cell's membrane potential, making it more negative than the resting potential. It occurs when specific ion channels open, allowing the flow of ions out of the cell. This makes the cell less likely to reach the threshold for an action potential.
Step-by-step explanation:
Hyperpolarization is a change in the membrane potential of a cell, making it more negative than the resting potential. It occurs when specific ion channels, such as potassium channels, open and allow the flow of ions out of the cell. This causes the cell to become more negative, making it less likely to reach the threshold for an action potential. For example, during repolarization of a neuron, after an action potential, potassium channels remain open, leading to a period of hyperpolarization.