what occurs in the synapse between neurons
synapse. the junction between the processes of two neurons or between a neuron and an effector organ, where neural impulses are transmitted by chemical means. The impulse causes the release of a neurotransmitter (e.g. acetylcholine or norepinephrine) from the presynaptic membrane of the axon terminal.ynapse. SYNAPSE: Axon terminal synapse. The space between the junction of two neurons in a neural pathway, where the termination of the axon of one neuron comes into close proximity with the cell body or dendrites of another.