The substance inside red blood cells that binds to oxygen and carries it from the lungs to the tissues.


... Why get tested?
If you have anemia (too few red blood cells) or polycythemia (too many red blood cells), to assess the severity of these conditions, and to monitor their response to treatment

When to get tested?
As part of a complete blood count (CBC), which may be ordered for a variety of reasons

Sample required?
A blood sample drawn from a vein in your arm or by a fingerstick (children and adults) or heelstick (newborns)
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3-dimensional structure of hemoglobin. The four subunits are shown in re ...
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