Ask a Teacher

two types of nervous system?with figures.

The nervous system

The brain and spinal cord together form the central nervous system. Nerves carry electrical impulses from the central nervous system to all parts of the body, making muscles contract or glands produce enzymes or hormones.

Glands and muscles are called effectors because they go into action when they receive nerve impulses or hormones. The biceps muscle is an effector which flexes the arm; the salivary gland is an effector which produces saliva when it receivers a nerve impulse from the brain.

The nerves also carry impulses back to the central nervous system from receptors in the sense organs of the body. These impulses from the eyes, ears, skin etc. make us aware of changes in our surroundings or in ourselves. Nerve impulses from the sense organs to the central nervous system are called sensory impulses; those from the central nervous system to the effectors, resulting in action, are called motor impulses.

The nerves which connect the body to the central nervous system make up the peripheral nervous system.