Nervous system

Brain and spinal cord together form central nervous system.The nerves branch off from central nervous system to all parts of body.The spinal cord contains nerves that carry messages between brain and body.The basic working unit of nervous system is called a neuron ( nerve cell ).

NEURON:-

                     Neurons are long,thin or a metre long. A neuron consists of cell body containing a nucleus and special extentions called axons and dendrites.Dendrites bring information to cell body while axons take information away from cell body.Messages travel along nerve cells as tiny electrical signals called impulses.         

There are two types of nerve cells.

1 Sensory nerve cells

2 Motor nerve cells

Motor nerve cell:-

                              They carry impulses from central nervous system to muscles and glands.

Sensory nerve cells:-

                               They carry impulses from sense receptors around the body to the central nervous system.