Properties of the Lungs-- Compliance, Elasticity, Resistance, and Surface Tension

Practice: Albuterol is β2 adrenergic receptor agonist used to treat asthma attacks; when it binds to β2 receptors on smooth muscle cells in the walls of airways it causes the smooth muscle cells to relax, leading to bronchodilation. Which of the following variables in Poiseuille’s Law is directly affected by the activity of albuterol and what is the resulting effect on resistance to flow (R) through the airways?

Practice: Two alveoli are next to each other in the lungs, connected by a bronchiole. Alveolus X has radius of 5; alveolus Y has a radius of 10. In which direction is air likely to flow?