What is the primary role of the trachea?

• A. To absorb oxygen into the bloodstream
• B. To serve as a passageway for air
• C. To produce sound during phonation
• D. To connect the lungs to the diaphragm

Answer: (B)

The primary role of the trachea is to serve as a passageway for air. It is a crucial part of the respiratory system that allows air to flow between the larynx and the lungs. The trachea is structured to remain open, ensuring that air can move freely in and out during inhalation and exhalation. Its walls are reinforced with cartilage, which prevents collapse and keeps the airway clear for efficient airflow.

The trachea does not absorb oxygen into the bloodstream; that function is primarily performed by the alveoli in the lungs. While the trachea is involved in the process of phonation as part of the airway, it does not produce sound directly; that function involves other structures, such as the vocal cords. Additionally, the trachea does not connect the lungs to the diaphragm, as the diaphragm is a muscle responsible for facilitating breathing by contracting and moving the lungs indirectly through changes in thoracic pressure. Thus, the trachea's essential role is simply to act as the air passageway.