In the synaptic end bulb, the action potential leads to the release of neurotransmitter. What links these two types of signals? A) The action potential triggers voltage-gated Na⁺ channels to open and the depolarization causes the vesicle walls to merge with the membrane. B) The action potential causes a change in the proteins on the vesicle membranes such that the vesicle binds to the cell membrane and begins exocytosis. C) The action potential triggers voltage-gated Ca²⁺ channels to open and the Ca²⁺ that flows in starts a cascade of protein reactions that allows exocytosis of the neurotransmitters. D) The action potential causes K⁺ to leave during repolarization and the decrease in K⁺ concentration triggers vesicles to bind to the membrane, releasing their contents.

Question

Quizplus · Accepted Answer

The action potential triggers the opening of voltage-gated Ca2+ channels, causing an influx of Ca2+ into the synaptic end bulb. This increase in Ca2+ concentration activates a cascade of protein reactions that leads to the fusion of the vesicle membrane with the cell membrane, and the release of neurotransmitter into the synaptic cleft.

In the Synaptic End Bulb, the Action Potential Leads to the Release