Action potential has a refractory period that divides in two: relative and absolute. Relative refractory period allows the generation of another AP but needs a greater initial despolarization to reach the excitation threshold. Absolute refractory period cannot generate another action potential no matter how strong the stimulus is.
The neurotransmitters was released from axon termianl
Explanation:
neurotransmitters are released from the axon terminal when their vesicles "fuse" with membrane of the axon terminal, spilling the neurotransmitter into the synaptic cleft.