The Respiratory System

at a Glance

Jeremy Ward, Jane Ward and Richard Leach

Multiple Choice: Chapter 19 Lung defence mechanisms

Question 19.1. Physical defences in the upper airways

a include cilia in the nasopharynx that catch large particles
b prevent particles greater than 1 μm entering the bronchi
c include humidification of air to prevent the epithelium from drying out
d are independent of mucus.