NREMT Paramedic Practice

What is the physiological role of bicarbonate in maintaining pH balance?

1. It serves as a source of oxygen.

2. It helps to buffer acids and bases.

3. It regulates carbon dioxide production.

4. It is a waste product of metabolism.

The correct answer is: It helps to buffer acids and bases.

Bicarbonate plays a crucial role in maintaining pH balance within the body by functioning as a buffer for acids and bases. In biological systems, the pH level is tightly regulated to ensure that enzymatic processes and cellular functions occur optimally. Bicarbonate ions (HCO3-) can neutralize excess hydrogen ions (H+) in acidic conditions, thereby decreasing acidity and raising pH. Conversely, in basic conditions, bicarbonate can donate hydrogen ions, helping to lower pH and increase acidity. This dynamic equilibrium allows bicarbonate to effectively stabilize the pH of blood and other bodily fluids, making it essential for homeostasis. The other options relate to different physiological processes that are not directly involved in the buffering capacity of bicarbonate. For instance, while carbon dioxide production is part of normal metabolism and can influence bicarbonate levels, bicarbonate itself does not directly regulate CO2 production. Additionally, bicarbonate does not serve as a source of oxygen, nor is it classified as a waste product of metabolism; rather, it is a critical component in the body’s acid-base homeostasis.