<P> The nervous system is defined by the presence of a special type of cell -- the neuron ( sometimes called `` neurone '' or `` nerve cell '' ) . Neurons can be distinguished from other cells in a number of ways , but their most fundamental property is that they communicate with other cells via synapses , which are membrane - to - membrane junctions containing molecular machinery that allows rapid transmission of signals , either electrical or chemical . Many types of neuron possess an axon , a protoplasmic protrusion that can extend to distant parts of the body and make thousands of synaptic contacts ; axons typically extend throughout the body in bundles called nerves . </P>
what part of the nervous system is found throughout the body
axons typically extend throughout the body in bundles called nerves