Which is TRUE about the initial segment of an axon? A)Its threshold potential is more positive than that of the cell body and dendrites. B)Its threshold potential is more negative than that of the cell body and dendrites. C)Synapses far from the initial segment are more effective in influencing whether an action potential will be generated in the axon than are synapses close to the initial segment. D)It is the region where neurotransmitter vesicles are docked and ready to be released by exocytosis. E)It can only conduct graded potentials because it lacks voltage-gated Na⁺ channels.

Question

Quizplus · Accepted Answer

The initial segment of an axon has a lower threshold potential than the cell body and dendrites, meaning that it requires less depolarization to trigger an action potential. This is due to the high density of voltage-gated ion channels, particularly sodium channels, in the initial segment.

Which Is TRUE About the Initial Segment of an Axon