Neuron, Structure, Function and Classification

Neuron

Neuron considered a basic unit and the building block of nervous system. Nervous system consists of trillion of neurons. Neuron is a source of transmission of information between brain and body. They are specialized cells, perform the function of receiving, processing and moving information from one place to another.

Functional Classification of Neuron

1. Sensory Neuron

2. Motor Neuron

3. Inter or Association Neuron

Sensory Neuron

Sensory neurons receive information from sensory organs i.e. muscles, glands and send it to central nervous system.

Motor Neuron

Motor neurons carry signals from the brain and spinal cord to the effected organ of body i..e muscles and glands.

Inter or Association Neuron

Inter neurons exist only in brain and spinal cord, where it serve as a linker between sensory and motor neurons. They receive information from sensory neurons and relay to motor neurons.

Structure of Neuron

No doubt neurons have not same size, shape and function but their basic structure is similar. When we examine a neuron in order to understand its anatomy, we find that neuron has following parts

1.      Dendrites

2.      Cell body or soma

3.      Axonal hillock

4.      Axon

5.      Myelin sheath

6.      Nodes of Ranvier

7.      Terminal Buttons

Structure	Function
Dendrites	Receive information from adjacent neuron (pre-synaptic neuron)
Cell Body	Its work as a control centre of neuron. Information received by dendrites, process in cell body then send to axon
Axonal Hillock	It is a junction between axon and cell body.
Axon	It is a tube like structure. Via axon information travel from cell body to terminal buttons.
Myelin sheath	Myelin sheath protects the axon. It also enhances the speed of nerve impulse.
Nodes of Ranvier	Enhance the speed of transmission
Terminal Buttons or Axon Terminal	Receive information form axon and send it to post synaptic neuron via synaptic cleft or synaptic gap