If an external stimulus acts to decrease the pH of the blood, this means that excess hydronium ions (H+) are being generated. If too much H+ is introduced into the blood, it will react with bicarbonate ions (HCO3-) to form carbonic acid (H2CO3), lowering the pH to normal levels around 7.4.
What is buffer solution?
A buffer solution is an aqueous mixture of a weak acid and its conjugate base, or vice versa, known more specifically as a pH buffer or hydrogen ion buffer. When a modest amount of a strong acid or base is applied to it, the pH hardly changes at all. A multitude of chemical applications use buffer solutions to maintain pH at a practically constant value. Numerous living systems use buffering to control pH in the natural world.
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