Light micrograph of the epithelium (lining cells) of an airway in the lung. The epithelium has cilia (the tiny hair like structures) that function to carry debris out of the airways. Beneath this respiratory epithelium are smooth muscle and fibrous cells which make up the wall of the airway. Haematoxylin and eosin stained tissue section. Magnification: 200x when printed at 10cm.