If you block Ca²⁺ channels on an axon,which will not occur?
A)The depolarization phase of the action potential
B)The repolarization phase of the action potential
C)The exocytosis of neurotransmitter
D)The graded potential
E)All of these will not occur

Question

Quizplus · Accepted Answer

Blocking Ca²⁺ channels on an axon would only affect the exocytosis of neurotransmitter, as Ca²⁺ ions are required for the fusion of vesicles containing neurotransmitter with the presynaptic membrane. The depolarization and repolarization phases of the action potential are driven by the movement of Na⁺ and K⁺ ions, respectively, and are not dependent on Ca²⁺. Graded potentials are also not dependent on Ca²⁺ channels. Therefore, choice C is the best option.

If You Block Ca²⁺ Channels on an Axon,which Will Not