An action potential has reached the synaptic end bulb, but there is no neurotransmitter release. This could be caused by A) failure of the voltage-gated k⁺ channels to open, thus preventing repolarization B) failure of the synaptotagmin to form channels for the neurotransmitter to cross the membrane C) failure of voltage-gated ca²⁺ channels to open, preventing ca²⁺ from entering the cell D) failure of kinesins to transport vesicles across the synaptic cleft

Question

Quizplus · Accepted Answer

Voltage-gated ca²⁺ channels must open to allow ca²⁺ to enter the synaptic end bulb and trigger neurotransmitter release. Failure of these channels to open can prevent neurotransmitter release.

An Action Potential Has Reached the Synaptic End Bulb, but There