Bird, secondary bronchus (LM, Medium)

Structure List Mucosal surface Submucosa Adventitia

There are only three generations of conducting airways in the bird lung: the trachea, the two primary bronchi which divide to provide air to each lung, and the secondary bronchi. This cross section is of the secondary bronchus and shows the mucosal surface with pseudostratified columnar epithelium and inpocketings of mucous cells. The submucosa is relatively narrow. The adventitia contains small pieces of cartilage, unlike the trachea which has complete rings.