Question

Which of the following statements concerning absolute refractory period is FALSE?

a.The relative refractory period immediately follows the absolute refractory period.
b.The absolute refractory period occurs during the after-hyperpolarization phase of the action potential.
c.The absolute and relative refractory periods assure the unidirectional spread of the action potential down the nerve fiber away from the initial site of activation.
d.The absolute refractory period corresponds to the time period during which the Na channel gates are closed.
e.The absolute refractory period refers to the period of time during which another action potential cannot be initiated.

Answer 1

The false statement concerning the absolute refractory period is that it occurs during the after-hyperpolarization phase of the action potential.

Step-by-step explanation:

The false statement concerning the absolute refractory period is option b. The absolute refractory period occurs during the peak action potential, not the after-hyperpolarization phase. During this period, the voltage-gated Na+ channels are inactivated and cannot be opened again for a brief time. As a result, another action potential cannot be generated until the channels return to their resting conformation.