What is the Central Nervous System (CNS)?
The Central Nervous System is the most significant unit in an organism. It is the ‘centre or the hub’ that initiates information, commands, coordinates and also impacts all activities within the body. This is why it is sometimes called the central processing area of the body. The Central Nervous System comprises mainly two parts: The spinal cord and the brain.
Brain
The brain is the most important organ and is divided into three parts.
- The forebrain
- Midbrain
- Hindbrain
It consumes around 30 percent of the oxygen. It interprets information from five senses within a body, as well as the internal organ stomach. Sometimes, the Central nervous system also includes the retina and optic nerves. These nerves connect directly to the brain tissues without any connecting nerve fibers. The spinal cord is a bridge that connects the brain to the body. If the spinal cord becomes damaged or inoperable, information flow will be disrupted.
Cells of Central Nervous System
There are several cells that play a major role in the proper functioning of the Central Nervous System. Dendrites, neurons and glial are the most important. These cells are connected to your brain and contain all the information.
Neurons
The fundamental unit of the brain, neurons, is responsible to transmit and process information to nerve cells, glands and muscles. There are approximately 100 billion neurons. Each neuron has a cell structure, an axon and dendrites that create extensions.
Dendrites
They are the specialised extension of the cell’s body. Their function is to receive and transmit information from cells. Dendrites can also be called processes.
Glial cell
There are three main types of glial cells. They provide the neutrons with metabolic and mechanical supports. These cells are:
- Astrocytes – They are star-shaped glial cells of the nervous system that conduct a variety of tasks, ranging from biochemical support of endothelial cells to brain and spinal cord repair and scanning following damage
- Microglia – It is a group of cells that make up around 10 to 15% of the brain’s total cells. They act as resistance cells. Their primary function is to protect the immune system by clearing out dead and dying cells. They also produce small molecules known as cytokines which are catalysts for the immune system
- Oligodendrocytes – The primary role of Oligodendrocytes, in the glial cell, is to support and wrap around the Axons. Myelin sheath, a fatty substance produced by Oligodendrocytes, allows nerve cells to quickly transmit and receive signals