In which location would you most likely find pseudostratified ciliated columnar epithelium with goblet cells?

• A. In the lining of serous cavities
• B. In the upper respiratory tract
• C. In the epidermis
• D. In the lining of the urinary bladder

Answer: (B)

Pseudostratified ciliated columnar epithelium with goblet cells is the respiratory mucosa that lines the conducting airways, from the nasal passages down through the trachea and into the bronchi. The cells appear layered, but each cell contacts the basement membrane, and they typically carry cilia on their surface along with scattered goblet cells that secrete mucus. The cilia beat to move mucus and trapped particles out of the airways, while goblet cells provide the mucus layer that captures debris and pathogens. This combination is characteristic of the upper respiratory tract, where cleaning and humidifying the inhaled air are essential. In contrast, serous cavities are lined by simple squamous epithelium, the epidermis by stratified squamous keratinized epithelium, and the urinary bladder by transitional epithelium designed to stretch.