Respiratory bronchiole

Respiratory bronchiole
Diagram of the alveoli with both cross-section and external view.
Schematic longitudinal section of a primary lobule of the lung (anatomical unit); r. b respiratory bronchiole; al. d alveolar duct; at atria; a. s alveolar sac; 'a' alveolus or air cell; p. a.: pulmonary artery; p. v pulmonary vein; l lymphatic; l. n lymph node.
Latin	bronchioli respiratorii
Gray's	subject #240 1098
Code	TH H3.05.02.0.00018

The respiratory bronchioles are the narrowest airways of the lungs, one fiftieth of an inch across.^[1] The bronchi divide many times before evolving into the bronchioles. The bronchioles deliver air to the exchange surfaces of the lungs.^[2] They are interrupted by alveoli which are thin walled evaginations. Alveolar ducts are distal continuations of the respiratory bronchioles.

Additional images

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  Part of a secondary lobule from the depth of a human lung, showing parts of several primary lobules.

References

External links

• Diagram at davidson.edu
• Respiratory+bronchioles at eMedicine Dictionary
• BU Histology Learning System: 13606loa