Respiratory System
©1996 University of Kansas Medical Center
Department of Anatomy and Cell Biology
Trachea
- Pseudostratified columnar, ciliated epithelium
- Goblet cells
- Sero-mucous glands
- Cartilage rings
Bronchi
- Pseudostratified columnar, ciliated epithelium (shorter)
- Goblet cells (fewer)
- Sero-mucous glands
- Cartilage
- Smooth muscle
Bronchioles
- Simple columnar or cuboidal & ciliated epithelium
- No goblet cells
- Smooth muscle (relatively abundant)
- Clara cells
Respiratory Bronchiole
- Simple cuboidal, ciliated epithelium (shorter)
- Clara cells
- Alveolar openings
Alveoli
- Type I Pneumocyte
- flattened for gas exchange
- covers 95% of alveolar surface (but only accounts for about 40% of pneumocyte population)
- Type II Pneumocyte
- cuboidal
- produces surfactant
- constitutes about 60% of the pneumocytes (but only 5% of the surface area)