Carbon dioxide (CO₂)is readily soluble in water, according to the equation CO₂ + H₂O ↔ H₂CO₃. Carbonic acid (H₂CO₃)is a weak acid. Respiring cells release CO₂ into the bloodstream. What will be the effect on pH of blood as that blood first comes in contact with respiring cells?

Question

Quizplus · Accepted Answer

When CO₂ is released by respiring cells, it quickly dissolves in the bloodstream and forms carbonic acid through the equation CO₂+H₂O↔H₂CO₃. Carbonic acid is a weak acid, and it can dissociate slightly to release hydrogen ions (H+) and bicarbonate ions (HCO₃-). This bicarbonate can then act as a buffer to maintain a relatively constant pH. However, the formation of carbonic acid also increases the concentration of hydrogen ions, causing a slight decrease in pH. Therefore, the correct answer is A as blood pH will decrease slightly.

Carbon Dioxide (CO₂)is Readily Soluble in Water, According to the Equation