Explain the structure of a neuron.

Explanation

A neuron or nerve cell is the structural and funtional unit of the nervous system. It consists of Cyton, Dendrites and Axon.
(a) Cyton : Cyton has a central nucleus with the abundant cytoplasm called neuroplasm. The cytoplasm has large granular body called Nissel.s granules and the other cell organelles like mitochondria, ribosomes, lysosomes , and endoplasmic reticulum.
(b) Dendrites : These are the numerous branched cytoplasmic processes, that project from the surface of the cell body. They conduct nerve impulses, towards the cyton.
(c ) Axon : The axon is a single, elongated, slender projection. The end of axon terminates as fine branches, which terminate into knob like swellings called synaptic knob. The plasma membrane of axon is called axolemma, while the cytoplasm is called axoplasm. it carries impulses away from the cyton. The axon may be covered by a protein sheath called myelin sheath, which is further covered by a layer of Schwann cells called Neurilemma. Myelin sheath breaks at intervals, by depressions called Nodes of Ranvier. The region between the nodes is called as internode.