Along with sodium bicarbonate, what substance contributes significantly to the base amount in the blood?

Sodium bicarbonate is a crucial component of the body's buffering system, which helps maintain acid-base balance in the blood. Hemoglobin plays an essential role in this process as well because it can bind to hydrogen ions (H+) and carbon dioxide (CO2), thus helping to regulate blood pH. When hemoglobin releases oxygen to tissues, it can also absorb protons, reducing acidity and ultimately contributing to the buffering capacity of blood.

While dissolved oxygen concentration, inorganic phosphorus, and organic phosphates have various roles in the body's physiology, they do not significantly affect the buffering capacity of the blood to the same extent as hemoglobin. Dissolved oxygen is vital for cellular respiration but does not have a direct role in acid-base balance. Inorganic and organic phosphates can act as buffers, but their contribution is less significant than that of hemoglobin within the context of blood pH and base amount. Therefore, hemoglobin's ability to interact with acidic components places it at the forefront of the substances that collectively maintain the base status in the blood along with sodium bicarbonate.