central and peripheral nervous system

The central nervous system (CNS) is the control center of the body, consisting of the brain and spinal cord.

Reflex actions are quick, involuntary responses to stimuli that help prevent injury and are essential for survival.

Sensory neurons carry messages to the central nervous system.

An involuntary action is a movement that you cannot control, such as reflexes.

A voluntary action is a movement that you can control, such as deciding to move your arm.

Motor neurons carry messages from the central nervous system to muscles, enabling movement.

The brain processes information, controls thoughts, emotions, and coordinates actions.

The spinal cord transmits messages between the brain and the rest of the body.

A stimulus is any change in the environment that can provoke a response.

A response is the reaction of an organism to a stimulus.