The neurons system is made up of highly specialized cells called as neurons. A neuron is composed of three main parts, namely cell body or cyton, dendrite and axon.
(i) Cyton It contains a well-defined nucleus, surrounded by granular cytoplasm called neuroplasm and all the cell organelles along with, Nissl's granules. Only centrosome is absent because nerve cells have lost the ability to divide.
(ii) Dendrites These are branched cytoplasmic projections of cyton known as the dendrons which receives nerve impulses.
Fig.Structure of Neuron
(iii) Axon: It is a very long process and projects from a part of cyton axon hillock. The lower end of the axon is branched and each branch terminates as a bulb like structures called nerve endings which have swollen synaptic knobs. There knobs possess synaptic vesicles, which store neurotransmitters. The axons transmit nerve impulses away from the cell body to a synapse or to a neuromuscular junction.
