What is the primary function of the nervous system?

The primary function of the nervous system is to transmit signals throughout the body, facilitating communication between different parts of the body and coordinating responses to internal and external stimuli. This system is composed of the brain, spinal cord, and peripheral nerves, which work together to convey sensory information, control motor responses, and manage complex processes such as thought and memory.

The nervous system enables quick responses to changes in the environment, which is vital for survival. For example, when you touch something hot, sensory neurons send signals to the brain, which processes this information and sends signals back to activate motor neurons to withdraw your hand quickly. This ability to quickly transmit signals sets the nervous system apart from other systems in the body that have different primary functions, such as digestion or transportation of gases.