What is the primary role of the respiratory system in the body?

The primary role of the respiratory system is to facilitate gas exchange, specifically the intake of oxygen and the release of carbon dioxide. This process occurs in the alveoli of the lungs, where oxygen from inhaled air diffuses into the bloodstream, and carbon dioxide, a waste product of cellular metabolism, diffuses from the blood into the lungs to be exhaled. This gas exchange is vital for maintaining the body's oxygen levels and removing carbon dioxide, which is crucial for regulating the body's pH and overall metabolic function.

Additionally, the efficiency of gas exchange is essential for sustaining cellular respiration, the process by which cells produce energy. Without a properly functioning respiratory system, oxygen levels would decrease, leading to cellular dysfunction and potentially life-threatening conditions.