Lung Microanatomy

Question 1

How is pulmonary blood flow distribution affected by gravity?

Answer 1

Flow has a uniform distribution when supine. When standing the highest parts of the lung have collapsed pulmonary vessels and become dead space, and the lowest parts of the lung are overperfused.

Question 2

What are the layers of conducting structure walls?

Answer 2

Epithelium- psuedostratified ciliated columnar epithelium and goblet cells (sweep mucus and produce mucus)
Smooth muscle (movement)
Outer connective tissue- cartilage (structure)

Question 3

How do the lungs protect against infections?

Answer 3

Cilia move mucus out of the lungs
Mucus traps small particles and pathogens
Mobile alveolar macrophages ingest and kill deposited particles or pathogens.