Lobular bronchioles

Bronchioles 11-13 8,192 0.8 2.7 44.5 level airways enter the lobules as defined by a strong elastic lobular limiting membrane Not named contain no cartilage, mucus secreting elements, or cilia. Tightly... 

In the bronchi, the deficiency results in the disappearance of the normal ciliated epithelium, which normally prevents the penetration of bacteria in the bronchial wall. Thus, in vitamin A deficiency the infectious agents find their way deep within the ramification of the bronchial tree, and severe bronchitis, bronchiolitis, and lobular pneumonia result. 

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