Osmosis video - Trachea and bronchi histology

The trachea is the large airway that extends from the larynx and divides into the two primary bronchi. The trachea and bronchi are lined with respiratory epithelium, a specialized type of epithelial tissue that functions to protect the lungs from inhaled particles and microorganisms. The tracheal and bronchial walls share a lot of characteristics. They both contain ciliated pseudostratified columnar epithelium with goblet cells, seromucous glands, smooth muscle, and cartilaginous support. Some of their main differences include the trachea's unique C-shaped cartilage rings with smooth muscle that connects the two ends of the ring, whereas the bronchi have interconnected cartilage plates instead. Also, the bronchi have shorter epithelial cells, fewer goblet cells, and fewer seromucous glands compared with the trachea.