Search results
Results From The WOW.Com Content Network
Collateral ventilation is a back-up system of alveolar ventilation that can bypass the normal route of airflow when airways are restricted or obstructed. The pathways involved include those between adjacent alveoli ( pores of Kohn ), between bronchioles and alveoli (canals of Lambert), and those between bronchioles (channels of Martin).
Within the lungs, the ventilation process specifically involves organs like respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli. For the perfusion process, the circulatory organs of the cardiovascular system such as the heart, pulmonary arteries, pulmonary veins, and alveolar capillaries are involved.
The ducts number between two and eleven from each bronchiole. [10] Each duct opens into five or six alveolar sacs into which clusters of alveoli open. Each terminal respiratory unit is called an acinus and consists of the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli. New alveoli continue to form until the age of eight years.
alveolar duct. alveolar sac. alveolus; At each division point or generation, one airway branches into two smaller airways. The human respiratory tree may consist on average of 23 generations, while the respiratory tree of the mouse has up to 13 generations. Proximal divisions (those closest to the top of the tree, such as the bronchi) mainly ...
A further complication in the case of the alveolar glands may occur in the form of still smaller saccular diverticuli growing out from the main sacculi. The term "racemose gland" [2] is used to describe a "compound alveolar gland" or "compound acinar gland." [3] Branched alveolar glands are classified as follows:
The bronchioles (/ ˈ b r ɑː ŋ k i oʊ l s / BRONG-kee-ohls) are the smaller branches of the bronchial airways in the lower respiratory tract.They include the terminal bronchioles, and finally the respiratory bronchioles that mark the start of the respiratory zone delivering air to the gas exchanging units of the alveoli.
Alveolar lung disease may be divided into acute or chronic. Causes of acute alveolar lung disease include pulmonary edema (cardiogenic or neurogenic), pneumonia (bacterial or viral), systemic lupus erythematosus, [2] bleeding in the lungs (e.g., Goodpasture syndrome), [3] idiopathic pulmonary hemosiderosis, [4] and granulomatosis with polyangiitis.
Thus, it includes the alveolar ducts, sacs, and alveoli but not the respiratory bronchioles. [30] The unit described as the secondary pulmonary lobule is the lobule most referred to as the pulmonary lobule or respiratory lobule. [25]: 489 [31] This lobule is a discrete unit that is the smallest component of the lung that can be seen without aid ...