http://www.mult-sclerosis.org/synapse.htmlThe synapse consists of:The presynaptic terminal at the end of an axon. This contains tiny vesicles which contain neurotransmitters - the small molecules which carry the nerve impulse from the sending neuron to the receiving neuron.The synaptic cleft - a gap between the two neurons across which the neurotransmitters migrate.The postsynaptic terminal usually in the dendrites of receiving neurons. This contains receiving sites for the neurotransmitters.Nerve impulses are transmitted down to the presynaptic terminal in the axon of one neuron and across the synaptic cleft to the postsynaptic terminal in the dendrite of another neuron.Synapses do not only join axons to dendrites (axodendritic synapses) - they can also joins axons to other axons (axoaxonic synapses) or to the soma - the neuronal cell body - (axosomatic synapses).