Which system includes the brain and spinal cord and transmits signals to the rest of the body?

• A. Endocrine System
• B. Circulatory System
• C. Nervous System
• D. Digestive System

Answer: (C)

The nervous system enables rapid communication throughout the body by using the brain and spinal cord to process information and send signals to muscles and organs. It includes the central nervous system, which houses the brain and spinal cord, and the peripheral nervous system that carries signals to the rest of the body. Nerve impulses travel quickly along neurons to coordinate movements, reflexes, and processing of sensory information.

Hormonal signals of the endocrine system travel through the bloodstream and generally act more slowly, coordinating longer-term processes rather than rapid body-wide signaling. The circulatory system moves blood and nutrients but doesn’t primarily transmit neural signals. The digestive system focuses on breaking down food and absorbing nutrients, not on rapid communication with the body. Therefore, the system that includes the brain and spinal cord and transmits signals to the rest of the body is the nervous system.