Carbon dioxide transport

When blood flows through capillaries, carbon dioxide diffuses from the tissues into the blood. Some carbon dioxide is dissolved in the blood. A part of CO₂ reacts with hemoglobin and other proteins to form carbamino compounds. The remaining carbon dioxide is converted tobicarbonate and hydrogen ions through the action of RBC carbonic anhydrase. Most carbon dioxide is transported through the blood in the form of bicarbonate ions.

Carbon dioxide (CO₂), the main cellular waste product is carried in blood mainly dissolved in plasma, in equilibrium with bicarbonate (HCO₃^-) and carbonic acid (H₂CO₃). 86–90% of CO₂ in the body is converted into carbonic acid, which can quickly turn into bicarbonate, the chemical equilibrium being important in the pH buffering of plasma.Blood pH is kept in a narrow range (pH between 7.35 and 7.45)