Kaplan Nursing Entrance Practice Exam

Which of the following air passages is NOT involved in respiration?

1. Bronchioles

2. Trachea

3. Esophagus

4. Alveoli

The correct answer is: Esophagus

The esophagus is the passage that is not involved in respiration. Its primary function is to transport food and liquids from the mouth to the stomach, playing no role in gas exchange or breathing. In contrast, the bronchioles, trachea, and alveoli are all integral parts of the respiratory system. The bronchioles are small airways in the lungs that lead to the alveoli, where gas exchange occurs. The trachea is the main airway that conducts air entering the lungs. Comprising tiny air sacs, the alveoli are critical for the exchange of oxygen and carbon dioxide during respiration. Thus, their roles are directly connected to the process of breathing and gas exchange, differentiating them from the esophagus, which functions in the digestive system.