What is the relationship between the bronchi, bronchial tubes, and bronchioles? what function does it serve

The airways of the lungs. When a person takes in a breath of air, the air travels through the nose or mouth, into the larynx, then into the trachea, which is the main passageway into the lungs. The trachea divides into a right and left main bronchus. Each major bronchus then subdivides into smaller airway passages referred to as bronchi. As the airway passages make their way out to the lung tissue, the passages become smaller and are referred to as bronchioles. Eventually the bronchioles terminate into small collections of air sacs known as alveoli, which is where the actual exchange of CO2 and Oxygen occur.

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