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Carbon Dioxide

Carbon dioxide (CO2) is a waste product made when the body breaks down food for energy (metabolism). The kidneys and lungs regulate the levels of carbon dioxide, bicarbonate, and carbonic acid in the blood.

The blood carries carbon dioxide to the lungs, where it is exhaled. More than 90% of carbon dioxide in the blood exists in the form of bicarbonate (HCO3). The remainder of the carbon dioxide is either dissolved carbon dioxide gas (CO2) or carbonic acid (H2CO3).

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerR. Steven Tharratt, MD, MPVM, FACP, FCCP - Pulmonology, Critical Care Medicine, Medical Toxicology
Last RevisedNovember 7, 2011

WebMD Medical Reference from Healthwise

Last Updated: November 07, 2011
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