Trachea and primary bronchus

The epithelium lining the trachea and primary bronchi is respiratory epithelium, pseudostratified columnar with cilia and goblet cells. The basement membrane is frequently prominent beneath this epithelium. Elastic fibers/lamella are obvious in the lamina propria, while only the left image shows scattered smooth muscle nuclei in narrows bands. 1000x

The epithelium lining the trachea and primary bronchi is respiratory epithelium, pseudostratified columnar with cilia and goblet cells. The basement membrane is frequently prominent beneath this epithelium. Elastic fibers/lamella are obvious in the lamina propria, while only the left image shows scattered smooth muscle nuclei in narrows bands. 1000x

The epithelium lining the trachea and primary bronchi is respiratory epithelium, pseudostratified columnar with cilia and goblet cells. The basement membrane is frequently prominent beneath this epithelium. Elastic fibers/lamella are obvious in the lamina propria, while only the left image shows scattered smooth muscle nuclei in narrows bands. 1000x

In the left image, longitudinally oriented elastic fibers, typical for the respiratory system, are dispersed in the lamina propria.

Smooth muscle bands (red arrows) are indistinct, while only two smooth muscle nuclei (black arrows) are obvious.

Numerous blood vessels are still present to modulate incoming air temperature.

This image was taken of a slide from the University of Mississippi collection.