Which of the following will increase the speed of an action potential moving down an axon?
I. Action potentials move faster in larger-diameter axons.
II. Action potentials move faster in axons lacking potassium ion channels.
III. Action potentials move faster in myelinated axons.
A) only I and II
B) only II and III
C) only I and III
D) I, II, and III

Question

Quizplus · Accepted Answer

I is true, as larger diameter axons have less resistance and therefore the action potential moves faster. II is false, as potassium channels are essential in repolarization and action potential generation. III is true, as myelin insulation allows for saltatory conduction which speeds up the action potential. Therefore, only I and III are true statements.

Which of the Following Will Increase the Speed of an Action