Which is TRUE about the axon hillock of an axon?
A)Its membrane potential at threshold is more positive than that of the cell body and dendrites.
B)Its membrane potential at threshold is more negative than that of the cell body and dendrites.
C)Synapses far from the axon hillock are more effective in influencing whether an action potential will be generated in the axon than are synapses close to the axon hillock.
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

Which is TRUE about the axon hillock of an axon?
A)Its membrane potential at threshold is more positive than that of the cell body and dendrites.
B)Its membrane potential at threshold is more negative than that of the cell body and dendrites.
C)Synapses far from the axon hillock are more effective in influencing whether an action potential will be generated in the axon than are synapses close to the axon hillock.
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.

Quizplus · Accepted Answer

The axon hillock's membrane potential at threshold is more negative than that of the cell body and dendrites, making it a critical region for the initiation of action potentials due to its high density of voltage-gated Na+ channels. This allows it to act as a "decision point" for the initiation of action potentials, based on the summation of graded potentials reaching it from the cell body and dendrites.

Which Is TRUE About the Axon Hillock of an Axon