Alveolar ducts

Definition

Alveolar ducts are the fine tubular passages that connect the respiratory bronchioles to the alveolar sacs. They play a crucial role in the final stages of air passage before gas exchange occurs in the alveoli.

5 Must Know Facts For Your Next Test

1. Alveolar ducts are lined with simple squamous epithelium to facilitate gas exchange.
2. They lead into clusters of alveoli, which are essential for oxygen and carbon dioxide exchange.
3. Alveolar ducts are supported by smooth muscle fibers, elastic fibers, and collagen.
4. The transition from respiratory bronchioles to alveolar ducts marks the beginning of the respiratory zone.
5. The walls of alveolar ducts contain numerous alveoli, allowing for efficient gas diffusion.

Review Questions

Related terms

respiratory bronchioles:

Small airways that come after terminal bronchioles and lead into alveolar ducts.

alveoli:

Tiny air sacs at the end of alveolar ducts where gas exchange occurs between air and blood.

respiratory zone: The portion of the respiratory system where gas exchange takes place, including respiratory bronchioles, alveolar ducts, and alveoli.