The brain is the powerhouse of the body, even though it only makes up 2 per cent of the body’s weight. They are wrapped in a thin lining called meninges and bathed with cerebrospinal fluid (CSF). The brain and the spinal cord make up the central nervous system.
Unlike other cells in the body, neurones aren’t easily replaced if they die or are damaged by infection or injury. Messages jump the synapse from one neurone to the next, using special chemicals called neurotransmitters. The space between the bump and the dendrite is called a synapse. Each bump sits near to a dendrite from another neurone. The axon feathers out and has a number of bumps on it.
In many cases, the axon is coated by a specialised membrane called a myelin sheath. All neurones have finger-like projections called dendrites and a long fibre called an axon. Neurones are shaped differently depending on where they are in the body and what role they play. The basic building block of the nervous system is a nerve cell, or neurone. The nervous system uses both electrical and chemical means to send and receive messages. It also reacts to changes both outside and inside the body. The nervous system helps all the parts of the body to communicate with each other.