What type of cell is responsible for the exchange of gases in the respiratory system?

The alveolar cell is crucial for the exchange of gases in the respiratory system. Alveoli are tiny air sacs located in the lungs where the exchange of oxygen and carbon dioxide takes place. They have a very thin wall, composed of a single layer of epithelial cells, which allows for efficient diffusion of gases. Oxygen from the inhaled air passes through the walls of the alveoli into the bloodstream, where it binds to hemoglobin in red blood cells. Simultaneously, carbon dioxide in the blood diffuses through the walls of the alveoli to be exhaled.

Red blood cells play a key role in transporting oxygen once it has been absorbed, but they do not themselves facilitate the actual exchange of gases within the lung structure. White blood cells are part of the immune system and are involved in fighting infections, not gas exchange. Cartilage cells contribute to the structure and support of the respiratory pathways, such as in the trachea and bronchi, but they do not have a role in the exchange of gases either. Thus, alveolar cells are specifically designed for this vital function in the respiratory system.