Which is a function of the respiratory system?

Which is a function of the respiratory system?

• A. Gas exchange
• B. Blood filtration
• C. Protein synthesis
• D. Nerve conduction

Answer: (A)

Gas exchange is a function of the respiratory system, allowing oxygen from inhaled air to diffuse into the bloodstream and carbon dioxide to diffuse out to be exhaled. This happens mainly in the alveoli, where the thin respiratory membrane and nearby capillaries create a large surface area for diffusion driven by differences in partial pressures: oxygen moves into blood and binds to hemoglobin for transport, while carbon dioxide moves from blood to the lungs to be expelled. This process supports cellular respiration and helps maintain acid-base balance by regulating CO2 levels. The other options don’t fit the respiratory system’s role: blood filtration is done by the kidneys, protein synthesis occurs in cellular ribosomes, and nerve conduction is a function of the nervous system.

Gas exchange is a function of the respiratory system, allowing oxygen from inhaled air to diffuse into the bloodstream and carbon dioxide to diffuse out to be exhaled. This happens mainly in the alveoli, where the thin respiratory membrane and nearby capillaries create a large surface area for diffusion driven by differences in partial pressures: oxygen moves into blood and binds to hemoglobin for transport, while carbon dioxide moves from blood to the lungs to be expelled. This process supports cellular respiration and helps maintain acid-base balance by regulating CO2 levels. The other options don’t fit the respiratory system’s role: blood filtration is done by the kidneys, protein synthesis occurs in cellular ribosomes, and nerve conduction is a function of the nervous system.