Which buffer base is found in both plasma and erythrocytes?

The correct answer, inorganic phosphates, are found in both plasma and erythrocytes and play a significant role in buffering the blood. Inorganic phosphates, primarily in the form of hydrogen phosphate (HPO4²⁻) and dihydrogen phosphate (H₂PO₄⁻), contribute to the regulation of pH in the body by maintaining acid-base balance.

In erythrocytes, inorganic phosphates, along with other buffering systems, help maintain the appropriate pH level during carbon dioxide transport and the release of oxygen. This buffering action is crucial as it ensures that the environment remains conducive to the functioning of hemoglobin and the overall integrity of the red blood cells.

While organic phosphates, hemoglobin, and plasma proteins also have roles in buffering, only inorganic phosphates are consistently present in both plasma and red blood cells, making them uniquely significant in maintaining the acid-base equilibrium in the circulatory system.