The fundamental cellular communication unit of the nervous system is the neuron or nerve cell. The neuron consists of the cell body which contains the nucleus and other components needed for the synthesis of cellular chemicals. Emanating from the cell body are processes called dendrites and these make contact with other nerve cells.
The cell body extends into a structure called the axon and terminating eventually into a structure called the pre-synaptic terminal. This nerve terminal is in close association with the post-synaptic cell which is either a dendrite of another neuron or it could be a muscle cell or gland.
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