Anatomy and Physiology II Practice Test

When a fixed acid is buffered, the amount of hydrogen ions in the blood actually decreases. Buffer systems in the body, such as bicarbonate, play a crucial role in maintaining pH levels by neutralizing excess acid. When a fixed acid enters the bloodstream, it dissociates into hydrogen ions and its corresponding conjugate base. The bicarbonate ions present in the blood can react with the excess hydrogen ions, forming carbonic acid, which can then dissociate into carbon dioxide and water, hence effectively reducing the concentration of free hydrogen ions.

This buffering action helps to stabilize the pH of the blood despite the addition of fixed acids. Therefore, it is essential to recognize that buffered systems work to mitigate changes in hydrogen ion concentration, leading to a decrease in the amount of free hydrogen ions when buffers are effectively engaged.