Respiratory bronchioles

Definition

Respiratory bronchioles are the smallest bronchioles that directly lead into the alveolar ducts. They play a crucial role in gas exchange within the lungs.

5 Must Know Facts For Your Next Test

1. Respiratory bronchioles mark the beginning of the respiratory zone.
2. They are lined with simple cuboidal epithelium transitioning to simple squamous epithelium.
3. Respiratory bronchioles contain smooth muscle and elastic fibers for support and flexibility.
4. They branch off from terminal bronchioles and further divide into alveolar ducts.
5. Gas exchange occurs in respiratory bronchioles due to their proximity to alveoli.

Review Questions

• What is the primary function of respiratory bronchioles?
• How do respiratory bronchioles differ structurally from terminal bronchioles?
• Where are respiratory bronchioles located in relation to alveolar ducts?

Related terms

Terminal Bronchioles: The last part of the non-respiratory conducting airway that leads to the respiratory bronchioles

Alveolar Ducts: The airway passages that connect respiratory bronchioles to alveolar sacs where gas exchange occurs

Alveoli: Tiny air sacs at the end of alveolar ducts where oxygen and carbon dioxide are exchanged between air and blood