Bronchiole
From Wikipedia, the free encyclopedia
| Bronchiole | |
|---|---|
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| Diagram of the alveoli with both cross-section and external view. | |
| 1. Trachea 2. Mainstem bronchus 3. Lobar bronchus 4. Segmental bronchus 5. Bronchiole 6. Alveolar duct 7. Alveolus | |
| Gray's | subject #240 1098 |
| Dorlands/Elsevier | Bronchioles/A04.411.125 |
The bronchioles are the first airway branches that no longer contain cartilage. They are branches of the bronchi, and are smaller than one millimetre in diameter.
There are no glands or cartilage in any of the bronchioles, and the epithelial cells become more cuboidal in shape.
Bronchioles divide until they become terminal bronchioles. After these the respiratory bronchioles have sporadic alveoli on their walls. Eventually the respiratory tract branches into alveolar ducts, then alveolar sacs.
[edit] Pathology
Bronchospasm, a life-threatening situation, occurs when the smooth muscular tissue of the bronchioles constricts, severely narrowing their diameter. Bronchospasm is commonly treated by oxygen therapy and bronchodilators.
The medical condition of inflammation of the bronchioles is termed bronchiolitis. Diseases of the bronchioles include asthma, bronchiolitis obliterans, respiratory syncytial virus infection, and influenza.
[edit] Additional images
Bronchi, bronchial tree, and lungs |
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lungs: right, left, lingula, apex, base, root, cardiac notch, cardiac impression, hilum, borders (anterior, posterior, inferior), surfaces (costal, mediastinal, diaphragmatic), fissures (oblique, horizontal) airway: trachea, carina, bronchi, main bronchus (right, left), lobar/secondary bronchi (eparterial bronchus), segmental/tertiary bronchi (bronchopulmonary segment), bronchiole, alveolar duct, alveolus pleurae: parietal pleura (cervical, costal, mediastinal, diaphragmatic), pulmonary pleura, pulmonary ligament, recesses (costomediastinal, costodiaphragmatic) |
