Which area of the airways lacks cartilage to maintain its structure?

The bronchioles are the area of the airways that lack cartilage in their structure. Unlike the larger airways, such as the trachea and bronchi, which have rings or plates of cartilage to maintain their shape and provide rigidity, bronchioles are smaller and more flexible. This lack of cartilage allows the bronchioles to have more dynamic changes in diameter, which is important for regulating airflow during respiration and for facilitating the distribution of air to the alveoli where gas exchange occurs.

The flexibility of bronchioles is critical because they can constrict or dilate in response to various stimuli, including bronchoconstriction occurring in asthma. This dynamic control is essential for proper lung function and helps to manage airflow resistance.