Final answer:
The Na/K ATPase plays a key role in maintaining the electrochemical gradient, but cannot repolarize the cell alone as K+ channel activity is also needed for this process.
Step-by-step explanation:
No, the Na/K ATPase alone cannot completely repolarize a cell as it requires the cooperative action of other ion channels to restore the resting potential.
The Na/K ATPase (sodium-potassium pump) is crucial for maintaining the electrochemical gradient across the cell membrane by actively transporting 3 Na+ ions out of the cell and 2 K+ ions into the cell against their concentration gradients, using ATP. This activity contributes to a negative resting membrane potential due to the net transfer of one positive charge out of the cell. However, during an action potential, Na+ channels open and allow Na+ ions to enter the cell, resulting in depolarization.
Subsequently, K+ channels open, allowing K+ ions to exit the cell, leading to repolarization. While the Na/K ATPase helps restore ion concentrations after multiple action potentials, it is the opening of K+ channels that primarily drives repolarization. The Na/K ATPase alone is not sufficient to repolarize the cell immediately following an action potential because the timing and duration of K+ channels opening are also necessary to re-establish the resting membrane potential.