Which of the following is described as a function of the respiratory system?

Which of the following is described as a function of the respiratory system?

• A. Gas exchange
• B. Regulation of blood pH
• C. Protection
• D. Digestion

Answer: (D)

Gas exchange is the function being tested. The respiratory system’s primary job is to supply oxygen to the blood and remove carbon dioxide produced by metabolism, accomplished at the alveolar-capillary membrane in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses outward to be breathed out. This process hinges on adequate ventilation, a large surface area, and thin membranes to allow efficient diffusion, and it directly supports cellular energy production. The system also helps regulate blood pH by adjusting CO2 levels and provides protective mechanisms for the airways, but digestion is not a function of the respiratory system.

Gas exchange is the function being tested. The respiratory system’s primary job is to supply oxygen to the blood and remove carbon dioxide produced by metabolism, accomplished at the alveolar-capillary membrane in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses outward to be breathed out. This process hinges on adequate ventilation, a large surface area, and thin membranes to allow efficient diffusion, and it directly supports cellular energy production. The system also helps regulate blood pH by adjusting CO2 levels and provides protective mechanisms for the airways, but digestion is not a function of the respiratory system.