The Nervous System:

Our nervous system, which is our body’s control system, is one of the most important systems in our body. It is made up of the brain, the spinal cord, the cranial nervous, and the peripheral nerves. So, the brain and network of these nerves control both conscious and unconscious activities of our body.

The brain receives, interprets, and sends nerve signals throughout our body, these nerve signals tell our muscles, organs, and every part of our body what to do and how to respond in various situations.

The spinal cord is a cylinder-shaped mass of nerve fibres that run down the centre passageway in the spine. The nerves that connect the brain to the head are called the cranial nerves. The group of nerves that branch off from the spinal cord at different levels are called the peripheral nerves.

Then, our nervous system is divided into three parts that work together. They are the central nervous system, the peripheral nervous system, and the autonomic nervous system.

The brain and spinal cord are together from the central nervous system. It deals with information (nerve signal or impulses) from our sense organs to the brain so that the brain can analyze this information and makes it possible for us (for our sense organs) to see, hear, smell, taste, and feel. The spinal cord also handles some automatic responses by itself.

The peripheral nervous system carries nerve signals from the central nervous system to our various muscles and organs. The autonomic (automatic or self-governing) nervous system regulates involuntary action such as heartbeat, digestion etc.

The peripheral nerves are divided into four groups called cervical spinal nerves, the thoracic spinal nerves, the lumber spinal nerves and the sacral spinal nerves. The group one (eight pairs) supplies the back of the head, the neck and shoulders, the arms and hands, and the diaphragm. The group two (twelve pairs) supplies the chest, some muscles of the back, and the parts of the abdomen.  The third group (five pairs) supplies the lower parts of the abdomen and the back, the buttocks, some parts of the external genital organs, and parts of the legs. And the fourth group (five pairs) supplies the thighs and lower parts of the legs, the feet, most of the external genital organs, and the area around the anus.