Answer to Question 1
ANS: D
The isothermic saturation boundary shifts deeper into the lungs when a person inhales through cold, dry air. In this case, the cilia function decreases and secretions are produced, increasing airway resistance. The turbulent convection increases contact between the inspired air and the mucosa.
Answer to Question 2
ANS: C
As the inspired air enters the nose, it is warmed by convection, not by conduction, and picks up water vapor from the moist mucosal lining by evaporation, not by condensation.