The document summarizes the structure and function of the respiratory system. It describes the conducting portion which includes the nasal cavity, pharynx, larynx, trachea, bronchi and bronchioles that warm and moisten air. It then describes the respiratory portion which includes respiratory bronchioles, alveolar ducts and alveoli where gas exchange occurs. It discusses the layers of the wall and types of epithelium found in the conducting portion, including ciliated columnar cells, mucous goblet cells, brush cells and basal cells.

1. RESPIRATORY SYSTEM Assoc. Prof. Dr. Karim Al-Jashamy MSU/IMS 2010

6. Respiratory Epithelium

7. Ciliated Columnar Cells

8. Surface of Respiratory Mucosa Ciliated cell Goblet cell Brush cell

9. Small Granule Cell (DNES) Electron micrograph of a cell of the diffuse neuroendocrine system. Note the accumulation of secretory granules (arrows) in the basal region of the cell. The Golgi complex seen in the upper part of the micrograph shows some secretory granules.

10. Nasal Passage

13. Nasal Mucosa E – Epithelium M – Mucous glands of lamina propria S – Serous glands of lamina propria V – Thin walled venules

14. Olfactory Mucosa

15. Sinuses The maxillary sinus frontal sinus sphenoidal sinus ethmoidal sinuses

17. Epithelium Lining of Sinus Thinner respiratory epithelium that contains few goblet cells.

18. Respiratory Structures

19. LARYNX Anterior Posterior

20. LARYNX

21. TRACHEA

22. Trachea Pseudostratified Epithelium Pseudostratified ciliated cells and mucous (goblet) cells are the two major components of the epithelium. Cilia beat at 1,000 to 1,500 cycles per minute resulting in movement of the mucus blanket at 0.5-1 mm /min in small airways and 5-20 mm/min in the trachea and main bronchi.

23. Trachea x10

24. Trachea x10

25. Trachea x40

26. Trachea

27. Mucous Glands in Upper Resp. Tract

28. Glands of Trachea x40