Final answer:
After an action potential, the neuron enters a refractory period during which it cannot initiate another action potential. This period allows the neuron's membrane to repolarize and return to its resting state before it can be responsive to another stimulus.
Step-by-step explanation:
During an action potential, after the initial depolarization where positive and negative ions switch places across the neuron's membrane, the process of repolarization restores the membrane to its resting state. This return to the resting state is achieved by closing the voltage-gated sodium channels and continuing the conductance of potassium channels. At the end of the action potential, there is a period called the refractory period, where the membrane cannot generate another action potential. During this refractory period, voltage-gated ion channels return to their resting configurations, with the assistance of the sodium-potassium ATPase which actively moves Na+ out of the cell and K+ back into the cell. This leads to repolarization of the membrane, setting the stage for the neuron to be ready for depolarization and another action potential should a sufficient stimulus be applied.