Following the path of air traveling through the respiratory system,as the bronchi get smaller,the amount of _____ in their walls decreases.
A)mucus
B)cartilage
C)smooth muscle

Question

Quizplus · Accepted Answer

As air travels through the respiratory system and reaches the smaller bronchi and bronchioles, the amount of cartilage in their walls decreases, making them more flexible but also more susceptible to collapse without the rigid support that cartilage provides.

Following the Path of Air Traveling Through the Respiratory System,as