Final answer:
The primary function of the respiratory system is to deliver oxygen and remove carbon dioxide. It exchanges gases like oxygen and carbon dioxide between the body and the environment.
Step-by-step explanation:
The primary function of the respiratory system is to deliver oxygen to the body's tissues and remove carbon dioxide, a waste product. The respiratory system exchanges gases such as oxygen and carbon dioxide between the body and its environment. This process is called respiration, which consists of two parts: bringing oxygen into the body and releasing carbon dioxide from the body.