What is distinctive about the trachea and bronchial linings?

The trachea and bronchial linings are distinct in their structure and function. The trachea is lined with pseudostratified ciliated columnar epithelium, which contains goblet cells that produce mucus to trap particles and pathogens. This lining also has C-shaped cartilage rings that provide structural support and prevent collapse. In contrast, the bronchial linings become progressively narrower and contain less cartilage and more smooth muscle, allowing for greater flexibility and regulation of airflow in the bronchi and bronchioles.