Most of the Carbon Dioxide in the Blood of Humans

Question

Most of the carbon dioxide in the blood of humans is transported
A)as dissolved CO2in plasmA.
B)as bicarbonate ion in plasma.
C)attached to hemoglobin in red blood cells.
D)attached to hemoglobin in plasma.
E)as carbonic acid.

Accepted Answer

The majority of carbon dioxide in the blood is transported as bicarbonate ions in plasma. When carbon dioxide enters the blood stream, it reacts with water to form carbonic acid, which then dissociates into bicarbonate ions and hydrogen ions. The bicarbonate ions are then transported in the plasma to the lungs, where they can be converted back into carbon dioxide and exhaled.