One of the reasons that action potentials only go in one direction, away from the cell body, is because
A) the adjacent prior segment of axon is still at +40mV.
B) voltage-dependent gates are limited in the frequency with which they can open.
C) the adjacent prior segment is still in refractory period.
D) the action potential temporarily disables the sodium-potassium pumps.

Question

Quizplus · Accepted Answer

The adjacent prior segment is still in refractory period, meaning that it is unable to produce another action potential immediately after firing. This ensures that the action potential can only move in the forward direction, away from the cell body. The other options are not correct - option A suggests that the prior segment is still depolarized, which is not necessarily true; option B is not relevant to the directionality of the action potential; and option D is incorrect because the sodium-potassium pumps are not involved in the propagation of action potentials.

One of the Reasons That Action Potentials Only Go in One