The release of acetylcholine from the terminal of a motor neuron is most directly linked to the ________.
A) entry of potassium into the axon terminal
B) exit of potassium from the axon terminal
C) entry of sodium into the axon terminal
D) exit of sodium from the axon terminal
E) entry of calcium into the axon terminal

Question

Quizplus · Accepted Answer

The release of acetylcholine from the terminal of a motor neuron is triggered by the entry of calcium into the axon terminal. When an action potential reaches the axon terminal, voltage-gated calcium channels open, allowing calcium to flow into the terminal. This calcium influx triggers the release of acetylcholine into the synaptic cleft, which then binds to the postsynaptic receptors and initiates muscle contraction.

The Release of Acetylcholine from the Terminal of a Motor