Which system is responsible for gas exchange in the body?

The respiratory system is specifically designed for gas exchange in the body, primarily involving the intake of oxygen and the expulsion of carbon dioxide. This process occurs in the alveoli, tiny air sacs within the lungs, where oxygen from inhaled air diffuses into the bloodstream, while carbon dioxide diffuses from the blood into the lungs to be exhaled. This system works in conjunction with the circulatory system to transport gases to and from cells throughout the body, but the actual exchange of gases occurs within the respiratory system itself.

In contrast, the digestive system is responsible for breaking down food and absorbing nutrients, while the nervous system controls bodily functions and responses, including those related to breathing but does not directly facilitate gas exchange. The circulatory system plays a vital role in transporting oxygen and carbon dioxide but relies on the respiratory system for the actual exchange process.