Oxygen

The Human Lungs
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2006, Pastel on Toned Underground, B42 x H30 cm
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The lung is the essential respiration organ in air-breathing animals. Their principal function is to transport oxygen from the atmosphere into the bloodstream, and to release carbon dioxide from the bloodstream into the atmosphere. This exchange of gases is accomplished in the mosaic of specialized cells that form millions of tiny, exceptionally thin-walled air sacs called alveoli.