How does the body compensate for metabolic acidosis?

• A. By reducing heart rate
• B. By decreasing respiration
• C. By increasing respiration
• D. By retaining carbon dioxide

Answer: (C)

In cases of metabolic acidosis, the body compensates primarily by increasing respiration. This physiological response occurs because respiratory compensation aims to reduce the acidity of the blood. When acidosis is present, there is an excess of hydrogen ions (H+) in the bloodstream, leading to a lower pH. In order to counteract this, the body increases the rate and depth of breathing (hyperventilation), which facilitates the exhalation of carbon dioxide (CO2).

CO2 reacts with water in the body to form carbonic acid, so by blowing off more CO2, the body reduces the concentration of carbonic acid and helps raise the blood pH towards a normal range. This respiratory response can help temporarily mitigate the effects of metabolic acidosis until the underlying cause of the condition can be addressed.

The other options, such as reducing heart rate, decreasing respiration, or retaining carbon dioxide, would not be suitable compensatory mechanisms for metabolic acidosis. Slowing the heart rate or breathing would potentially worsen the acidosis and is not an adaptive response in this situation. Similarly, retaining carbon dioxide would increase the acidity in the blood, exacerbating the condition rather than alleviating it.