The Primary Role of the Carbonic-Acid-Bicarbonate Buffer System is To

Question

The primary role of the carbonic-acid-bicarbonate buffer system is to
A) buffer stomach acid.
B) buffer carbonic acid formed by carbon dioxide.
C) limit pH changes caused by metabolic and fixed acids.
D) buffer the urine.
E) increase ventilation.

Accepted Answer

The carbonic-acid-bicarbonate buffer system helps to maintain pH homeostasis in the body by preventing drastic changes in pH caused by metabolic and fixed acids. This system works by converting excess hydrogen ions (H+) into carbonic acid (H2CO3) which then dissociates into bicarbonate ions (HCO3-) and hydrogen ions (H+). This helps to maintain a relatively constant pH in the blood and other bodily fluids. The other answer choices are incorrect because this system primarily functions in pH regulation, not in buffering stomach acid, urine, or increasing ventilation.