Nervous system is well developed in human and is composed of neurons or nerve cells. This system includes brain, spinal cord, sensory organs and nerves. The two important functions of the nervous system along with the endocrine system are conduction and co-ordination.
The brain is a complex organ which is placed inside the cranium. It is protected by a three layered tissue coverings called meninges. Brain has three regions namely fore brain, mid brain and hind brain. It is the controlling centre of the body.
It is the extension of medulla oblongata of the hind brain and is enclosed within the vertebral column. Spinal cord connects the brain to different part of the body through nerves.
The Functions of the Nervous System
1. Sensory Input
The conduction of signals from sensory receptors.
The interpretation of the sensory signals and the formulation of responses.
3. Motor output
The conduction of signals from the brain and spinal cord to effectors, such as muscle and gland cells.
Brain is said to store as many as 100 million bits of information in a life time.