Final answer:
The refractory period is the time after depolarization when the nerve membrane repolarizes, and it is a state where a neuron or muscle cell cannot generate another action potential.
Step-by-step explanation:
The time during which a nerve membrane repolarizes after depolarization is known as the refractory period. This period follows the transmission of an impulse in a nerve or muscle, allowing the neuron or muscle cell to regain its ability to transmit another impulse. During the refractory period, the membrane cannot produce another action potential. The voltage-sensitive ion channels return to their resting configurations while the sodium-potassium ATPase continually moves Na+ out of the cell and K+ into the cell, restoring the cell's resting state. This process of repolarization enables the cell membrane to once again be ready for depolarization, necessary for the transmission of subsequent action potentials.