Lung Flashcards
1
Q
What are the two phases of the mucociliary escalator?
A
Hypophase - lower layer of serous watery secretion, cilia propels mucus hypophase in upward direction.
Epiphase - upper mucus (viscous) secretion - traps & immobilises dust particles & bactera.
2
Q
What is the role of;
Terminal and respiratory bronchioles
Alveolar ducts and sacs?
A
- Particle removal / airflow regulation / limited GE.
- GE / o.2-0.4 uM wall thickness –> efficient gas exchange.
3
Q
How do type I and type II penumocytes differ?
A
TI - squamous, share common BM with blood vessel (40% but 90% of SA)
TII - cuboidal, secrete surfactant and stem cells (60 but represent only 10%).
