Question

Which of the following statements does not accurately describe the events involved in the propagation of an action potential?

(a) An initial influx of Na+ through a small cluster of channels causes local depolarization of the membrane.
(b) Local depolarization causes nearby Na+ channels to open.
(c) Channels in depolarized regions of the membrane are inactivated until the resting membrane potential is reestablished.
(d) The opening of transmitter-gated K+ channels helps to repolarize the membrane.

Answer 1

Channels in depolarized regions of the membrane are not inactivated until the resting membrane potential is re-established. The correct option is (c) Channels in depolarized regions of the membrane are inactivated until the resting membrane potential is reestablished.

Step-by-step explanation:

The correct statement that does not accurately describe the events involved in the propagation of an action potential is (c) Channels in depolarized regions of the membrane are inactivated until the resting membrane potential is re-established.

In reality, once the membrane potential reaches the threshold, voltage-gated Na+ channels open allowing the influx of Na+ ions, which leads to depolarization. These channels do not become inactivated until the membrane potential reaches a certain value, not until the resting membrane potential is re-established. The correct option is (c) Channels in depolarized regions of the membrane are inactivated until the resting membrane potential is re-established.