Exemplar Problems

Question:

Diffusion of gases occurs in the alveolar region only and not in the other parts of respiratory system. Why?

Answer:

Diffusion of Gases in the Alveolar Region: Gas exchange, specifically the diffusion of oxygen (O2) into the bloodstream and the diffusion of carbon dioxide (CO2) out of the bloodstream, primarily occurs in the alveolar region of the respiratory system. This is because the alveoli are tiny, thin-walled air sacs in the lungs where the exchange of gases between air and blood takes place. The alveoli provide a large surface area and thin membranes, which allow for efficient diffusion of gases. In contrast, other parts of the respiratory system, like the trachea, bronchi, and bronchioles, are primarily involved in air transportation and humidification but do not participate in gas exchange to the same extent.