Which term refers to the network that circulates blood and exchanges gases in the body?

• A. Cardiovascular System
• B. Digestive System
• C. Lymphatic System
• D. Nervous System

Answer: (A)

The cardiovascular system is the body's transport network, using the heart as a pump and a vast array of blood vessels to move blood throughout the body. This flow delivers oxygen from the lungs to tissues and brings carbon dioxide from tissues back to the lungs to be exhaled. Gas exchange occurs primarily in the lungs, where oxygen enters the blood and carbon dioxide leaves, and at tissue capillaries, where oxygen is delivered to cells and carbon dioxide is picked up for removal. The other options involve different roles: the digestive system handles nutrients, the lymphatic system supports fluid balance and immunity, and the nervous system coordinates signaling. So the term that refers to the network circulating blood and exchanging gases is the cardiovascular system.