Final answer:
The reaction helps to maintain a normal pH in the blood by using bicarbonate ions and carbonic acid as a buffering system.
Step-by-step explanation:
The reaction shown in your question helps to maintain a normal pH in the blood.
Bicarbonate ions (HCO3-) and carbonic acid (H2CO3) are present in the blood in a 20:1 ratio, which acts as a buffering system to prevent significant changes in pH. This buffering system is most efficient at buffering changes that would make the blood more acidic.
For example, when excess hydrogen ions (H+) are present, they can bind to bicarbonate ions, forming carbonic acid and removing hydrogen ions, thus moderating pH changes.