From the main airways, the branching tubes become progressively smaller. What are these smallest conducting airways called?

From the main airways, the branching tubes become progressively smaller. What are these smallest conducting airways called?

• A. Pharynx
• B. Bronchioles
• C. Alveoli
• D. Larynx

Answer: (B)

As air moves deeper into the lungs, the passageways get progressively smaller but still serve to conduct air rather than exchange gases. The smallest conducting airways are the bronchioles. They are the narrowest tubes in the conducting zone, carrying air to the areas where gas exchange begins, which happens in the respiratory bronchioles and ultimately in the alveoli beyond them. The other options don’t fit: the pharynx and larynx are part of the upper airway, and the alveoli are the sites of gas exchange, not conducting air. So bronchioles are the correct answer.

As air moves deeper into the lungs, the passageways get progressively smaller but still serve to conduct air rather than exchange gases. The smallest conducting airways are the bronchioles. They are the narrowest tubes in the conducting zone, carrying air to the areas where gas exchange begins, which happens in the respiratory bronchioles and ultimately in the alveoli beyond them. The other options don’t fit: the pharynx and larynx are part of the upper airway, and the alveoli are the sites of gas exchange, not conducting air. So bronchioles are the correct answer.