Neurotransmitter is released _____.
A)in response to an action potential depolarizing the presynaptic membrane
B)when threshold potential is reached
C)when enough voltage-gated sodium channels open

Question

Quizplus · Accepted Answer

Neurotransmitter is released in response to an action potential depolarizing the presynaptic membrane. When the action potential reaches the axon terminal, it causes voltage-gated calcium channels to open, allowing calcium ions to enter the axon terminal. The calcium ions cause synaptic vesicles containing neurotransmitter to fuse with the presynaptic membrane and release their contents into the synaptic cleft. Choices B and C are not accurate as threshold potential and voltage-gated sodium channels are not directly involved in neurotransmitter release.

Neurotransmitter Is Released _____