Neuron:- it is one of the basic functional units of the nerves system.a cell sepecilized to transmit electrical, nerves impulses and so carry information from one part of the body to another. each neuron has an enlarge portion, the cell body, containing the nucleus, from the body extend several process (dendrites) through pluses enters from their branches. a longer process the nerve fiber extends outward and carry impulses away from the cell body. this is normally unbranched except at the nerve ending. the point of contact of one neuron with another is known as synapse.