When an action potential reaches the presynaptic terminal,

A) calcium ions diffuse into the presynaptic terminal through voltage-gated ion channels.
B) acetylcholine moves into the presynaptic terminal.
C) a local potential is generated in the presynaptic terminal.
D) ligand-gated ion channels in the presynaptic terminal are opened.
E) nothing else happens.

Presynaptic Terminal

The end of a neuron from which neurotransmitters are released to communicate with another neuron at a synapse.

Action Potential

An action potential is a rapid and temporary electrical charge that travels along the membrane of a neuron, enabling the transmission of signals.

Calcium Ions

Essential ions within the body that play key roles in blood clotting, muscle contraction, and nerve function.