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How does carbonic anhydrase speed up carbon dioxide transport in the blood?

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Medical illustration of the human chest showing the lungs, diaphragm, ribs, trachea, bronchus, and bronchioles, with one lung cut away to reveal internal structures. — human respiratory system The lungs serve as the gas-exchanging organ for the process of respiration.

Carbonic anhydrase is an enzyme found within red blood cells that significantly accelerates the transport of carbon dioxide in the blood.12

While the natural conversion of carbon dioxide and water into carbonic acid is a relatively slow process, carbonic anhydrase catalyzes this reaction with such rapidity that it occurs in only a fraction of a second. By facilitating this conversion inside the red blood cell, the enzyme allows for the efficient production of bicarbonate ions (HCO $_{3}^{-}$ ), which are then transported into the plasma via the chloride shift. This mechanism enables the blood to carry a much larger volume of carbon dioxide than would be possible through simple dissolution alone.2