Final answer:
Each secondary bronchus supplies a bronchopulmonary segment of the lung, which is a subdivision of a lobe. The bronchial tree consists of the bronchi and bronchioles that terminate in alveoli for gas exchange. Note that tertiary bronchi supply the bronchopulmonary segments.
Step-by-step explanation:
Each secondary bronchi supplies a portion of the lung known as a bronchopulmonary segment. The respiratory system's bronchial tree is a sophisticated branching system comprised of the trachea, primary bronchi, secondary bronchi, and tertiary bronchi, which eventually give way to the bronchioles. Each lung is composed of lobes, with the right lung having three lobes (superior, middle, and inferior) and the left lung having two lobes (superior and inferior). Fissures separate these lobes. Within each lobe are multiple bronchopulmonary segments, and each segment receives air from its own tertiary bronchus and blood supply from its own artery.
The tertiary bronchi further branch into bronchioles, leading to the alveoli where gas exchange occurs. In addition, the muscular walls of the bronchioles can adjust airflow through the respiratory zone, and they lack cartilage unlike the larger bronchi. The structure and branching patterns allow for targeted treatments, such as the surgical removal of diseased bronchopulmonary segments with minimal impact on adjacent segments.