The release of neurotransmitter from the presynaptic terminal is most dependent on the influx of what ion?
A) sodium
B) potassium
C) chloride
D) calcium

Question

Quizplus · Accepted Answer

The release of neurotransmitter from the presynaptic terminal is primarily dependent on the influx of calcium ions through voltage-gated calcium channels. When an action potential reaches the presynaptic terminal, it triggers the opening of these channels, allowing calcium ions to enter the cell and cause the synaptic vesicles to release their contents (i.e., neurotransmitter molecules) into the synaptic cleft. Therefore, choice D (calcium) is the best answer.

The Release of Neurotransmitter from the Presynaptic Terminal Is Most