Oxygenated blood travels to the heart and the rest of the body
We breathe in oxygen (O2)
Carbon dioxide (CO2) is eliminated when we breathe out
Capillaries carry deoxygenated blood
Carbon dioxide (CO2) moves from the capillaries into the alveoli
Cells produce energy and a waste gas called carbon dioxide (CO2)
Oxygen (O2) moves from the alveoli into the blood capillaries
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