The nervous system has two great divisions: the central nervous system (CNS), which consists of the brain and the spinal cord, and the peripheral nervous system (PNS), which consists of nerves and small concentrations of gray matter called ganglia. The brain sends messages via the spinal cord to the body’s peripheral nerves, which control the muscles and internal organs.
The nervous system, essentially the body’s electrical wiring, is a complex collection of nerves and specialised cells knows as neutrons that transmit signals between different parts of the body. Vertebrates, animals with backbones and spinal columns, have central and peripheral nervous system. Let’s look at the types of nervous system :
- Cranial Nervous System – These are nerves that connect the brain to the eyes, mouth, ears and other parts of the head.
- Central Nervous System – This is the integration and command centre of the body. It consists of the brain, spinal cord and retina.
- Peripheral Nervous System – This consists of sensory neutrons, ganglia (cluster of neurons) and nerves that connect the central nervous system to arms, hands, legs and feet.
- Autonomic Nervous System – These are nerves that connect the central nervous system to the lungs, heart, stomach, intestines, bladder and sex organs.