Alveoli and Resistance to airflow

Question 1

What is the function of elastic fibers in the lungs?

Answer 1

Makes the tissue “spring back” and compress; creates collapsing pressure and makes respiration a passive process

Question 2

What are the alveoli composed of?

Answer 2

Primarily type I cells (simple squamous epi w/ thin basal lamina, no cilia); 5% type II (septal cells, round/cuboidal cells secrete surfactant that reduces surface tension); some macrophages