Question

required information an action potential arriving at the presynaptic terminal causes what to occur? multiple choice voltage - gated sodium ion channels open, and sodium ions diffuse into the cell. voltage - gated sodium ion channels open, and sodium ions diffuse out of the cell. voltage - gated calcium ion channels open, and calcium ions diffuse into the cell. acetylcholine diffuses into the cell. ligand - gated sodium channels open, and sodium ions diffuse out of the cell.

Explanation:

When an action potential arrives at the presynaptic terminal, voltage - gated calcium ion channels open. This allows calcium ions to diffuse into the cell. Calcium influx triggers the release of neurotransmitters. Sodium ion movement is more associated with the generation and propagation of action potentials within a neuron, not specifically at the presynaptic terminal arrival event. Acetylcholine is a neurotransmitter released from the presynaptic terminal, not diffusing into it. Ligand - gated channels are not the main event here.

Answer:

Voltage - gated calcium ion channels open, and calcium ions diffuse into the cell.