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Alveolar ducts and alveoli


Alveolar ducts and alveoli


         Terminal bronchioles get divided into many branches and several small ducts come into existence such ducts are called alveolar ducts which open in too much minute air sacs which are called alveoli. Air sacs or alveoli are covered by the net of cells. The air sacs are like the puffed bunches of grapes because of which the area of internal surface becomes enlarge very much where gases are exchanged. Their walls are unstratified by the simple acvemus epithelium.