Introduction to the Respiratory System

The Major Airways
It is important to be able to histologically distinguish:
  • trachea
  • bronchus
  • bronchiole
  • respiratory bronchiole
  • alveolar duct with smooth muscle rings
  • alveolus
Slides 92 (ovine) and 8 (canine)offer some interesting contrasts:



Slide 92 (Ovine)
Slide 8 (Canine)
-dissected trachea -partially in situ
-excellent pseudostratified columnar epithelium with kinocilia and mucous cells -metaplastic epithelium with patches of kinocilia, scanty mucous cells; mainly stratified columnar or squamous epithelium
-comparatively common glands; mucous, serous and mixed -few glands, mucous, serous and mixed
-blood vessels beneath epithelium are full of blood -blood mainly drained (exsanguinated) from tissue


Q: What histologic feature is diagnostic for trachea?


Return to modules On to lung proper