bronchiole


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Related to bronchiole: respiratory bronchiole, terminal bronchiole

bronchiole

 [brong´ke-ōl]
one of the successively smaller channels into which the segmental bronchi divide within the bronchopulmonary segments. adj., adj bronchi´olar.
respiratory b's the final branches of the bronchioles, communicating directly with the alveolar ducts; they are subdivisions of terminal bronchioles, have alveolar outcroppings, and themselves divide into several alveolar ducts.
Respiratory bronchiole. From Dorland's 2000.
( and see color plates.)
terminal bronchiole the last portion of a bronchiole that does not contain alveoli, i.e., one whose sole function is gas conduction; it subdivides into respiratory bronchioles.

bron·chi·ole

(brong'kē-ōl), [TA]
One of approximately six generations of increasingly finer subdivisions of the bronchi, all smaller than 1 mm in diameter, and having no cartilage in its wall, but relatively abundant smooth muscle and elastic fibers.
Synonym(s): bronchiolus [TA]

bronchiole

/bron·chi·ole/ (brong´ke-ōl) one of the finer subdivisions of the branched bronchial tree.
respiratory bronchioles  the final branches of the bronchioles.

bronchiole

(brŏng′kē-ōl′)
n.
Any of the fine, thin-walled, tubular extensions of a bronchus.

bron′chi·o′lar (-ō′lər) adj.

bronchiole

[brong′kē·ōl]
Etymology: L, bronchiolus, little windpipe
a small airway of the respiratory system extending from the bronchi into the lobes of the lung. There are two divisions of bronchioles: The terminal bronchioles passively conduct inspired air from the bronchi to the respiratory bronchioles and expired air from the respiratory bronchioles to the bronchi. The respiratory bronchioles function similarly, allowing the exchange of air and waste gases between the alveolar ducts and the terminal bronchioles. bronchiolar [brongkē′ələr] adj.
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Bronchioles

bronchiole

A conducting airway which begins at the last cartilaginous plate and ends at the last ciliated epithelial cell; bronchioli are any of 7–9 increasingly finer subdivisions of the bronchiolar tree (BT), measuring < 1 mm in diameter. In the distal BT, the respiratory epithelium becomes flatter, the ciliated cells fewer in number, the mucous glands less prominent and eventually disappear and, in the purely respiratory bronchioles, cuboidal nonciliated non-mucus-producing Clara cells appear.

Bronchiole types 
Respiratory bronchiole bronchiolus respiratorius MNA6
Any of 1–3 generations of ≤ 0.5-mm airways that connect terminal bronchioli to the alveolar ducts. Alveoli arise directly from the wall of RBs; the most distal RB is histologically characterised by an air space lined on one side by respiraotory epithelium and on the other by alveoli.
 
Terminal bronchiole bronchiolus terminalis NA6
Any of ±6 generations of purely conducting—i.e., nonrespiratory bronchioles—which connect; rare direct connections between TBs and alveoli may be seen, known as Lamberth’s canals.

bron·chi·ole

(brong'kē-ōl)
One of approximately six generations of increasingly finer subdivisions of the bronchi, each smaller than 1 mm in diameter, and having no cartilage in its wall, but relatively abundant smooth muscle and elastic fibers.
Synonym(s): bronchiolus [TA] .

bronchiole

One of the many thin-walled, tubular branches of the bronchi, which extend the airway to the terminal air sacs (alveoli). Bronchi have cartilaginous rings, bronchioles do not.

bronchiole

one of the smaller tubes branching off the two main bronchii in the lungs of higher vertebrates. See BREATHING and Fig. 81 .

Bronchiole

A thin air passage in the lung that branches off a larger airway.
Mentioned in: Bronchiolitis

bronchiole

subdivision of a bronchus

bron·chi·ole

(brong'kē-ōl)
One of approximately six generations of increasingly finer subdivisions of the bronchi, all smaller than 1 mm in diameter.

bronchiole (brong´kēōl),

n a terminal division of a bronchium.

bronchiole

one of the successively smaller channels (1 mm or less) into which the bronchi divide.

respiratory bronchiole
the final branch of a bronchiole, communicating directly with the alveolar ducts; a subdivision of a terminal bronchiole, it has alveolar outcroppings and itself divides into several alveolar ducts.
References in periodicals archive ?
In emphysema, a structural element (elastin) in the terminal bronchioles is destroyed leading to collapse of the airway walls and inability to exhale "stale" air.
Lungs of nitrofen-exposed pups had 30% fewer terminal bronchioles than did controls, and they were developmentally immature (Leinwand et al.
Scarce attachment of avian influenza viruses to bronchioles and alveoli of harbor seals is consistent with low pathogenicity of these viruses for harbor seals during experimental infection (4-6).
If there are emphysematous changes in the lung involving the loss of elastic and reticular fibers from the release of excess trypsin from macrophages keyed by the response to particulate deposition, as in a smoker's lung, the bronchioles will not remain patent as the lung volume approaches residual volume (RV) and as the trans-pulmonary pressures increase.
This structure is called the bronchial tree as it resembles an upside-down tree with the trachea as "trunk," bronchi as "branches," and bronchioles as "twigs.
Histologically, diffuse panbronchiolitis is characterized by transmural infiltration of the bronchiole and surrounding lung interstitium with foamy macrophages, plasma cells, and lymphocytes.
The minimum criteria necessary for a diagnosis of asbestosis were the finding of "discrete foci of fibrosis in the walls of respiratory bronchioles associated with accumulations of asbestos bodies" in histologic sections.
Some of the bronchioles and adjacent alveoli walls also demonstrated a mild chronic interstitial inflammatory infiltrate as well as interstitial fibrosis and hyperplasia of the overlying alveolar epithelial cells.
The TB region is defined as the region from the trachea down to the terminal bronchioles (Overton et al.
Clara cells remained at the bifurcation of the bronchiole throughout the period.
The functional unit of the lung, the acinus, is composed of the terminal bronchiole and the air spaces it supplies (12).
All orientations of respiratory bronchioles were included; however, the generation of each airway level was clearly identified based on position from the terminal bronchiole and/or first-generation respiratory bronchiole.