Lung bronchiole and alveoli. Coloured scanning electron micrograph (SEM) of a bronchiole (upper centre) and a cluster of alveoli (air sacs, grey) in a

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Lung bronchiole and alveoli. Coloured scanning electron micrograph (SEM) of a bronchiole (upper centre) and a cluster of alveoli (air sacs, grey) in a human lung. The bronchiole carries inhaled air from the upper airway to the alveoli in the lung. Each alveolus is a site for gas exchange between the air in the air sac and the blood in adjacent capillaries (not seen). Oxygen diffuses into the blood for delivery to cells for respiration, and carbon dioxide diffuses out of the blood to be exhaled. Magnification: x220 when printed at 10cm wide.

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Size: 4000px × 4000px
Photo credit: © EYE OF SCIENCE/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: air, airway, airways, alveoli, alveolus, anatomy, body, breathing, bronchiole, coloured, exchange, gas, gaseous, human, lung, lungs, passage, pulmonary, respiration, respiratory, sac, sacs, sem, system