The respiratory system is responsible for supplying the body with what essential gas?

The respiratory system is primarily responsible for supplying the body with oxygen. This essential gas is crucial for cellular respiration, a process that occurs in our cells to produce energy. During respiration, oxygen is inhaled into the lungs and then transferred into the bloodstream, where it is delivered to cells throughout the body. In return, carbon dioxide, a byproduct of cellular respiration, is transported back to the lungs to be exhaled. While nitrogen and hydrogen are present in the air and play various roles in biological systems, they are not the primary focus of the respiratory process. Hence, oxygen is the essential gas that the respiratory system specifically facilitates for the body's metabolic needs.