Final answer:
Acid is a H+ donor, with Carbonic acid mainly eliminated in the lungs as CO2 and a smaller amount eliminated in the kidneys. The bicarbonate buffer system helps to maintain pH balance by regulating carbonic acid and bicarbonate levels through respiratory and renal processes.
Step-by-step explanation:
Acid is a H+ donor, and Carbonic acid 13000 mEq is eliminated in the lungs, and 30-40 mEq is eliminated in the kidneys.
Acid-base homeostasis in the body involves the bicarbonate buffer system to regulate pH levels. Carbonic acid dissociates to release H+ ions and bicarbonate (HCO3-) ions. This system captures free ions, preventing significant changes in pH. The majority of carbonic acid is eliminated via the lungs as CO2 when we exhale. The kidneys manage bicarbonate reabsorption and elimination, balancing the acid-base in the body.
The bicarbonate buffer system is crucial because it deals with metabolic wastes, including acids like lactic acid and ketones. As such, there is typically a 20:1 ratio of bicarbonate to carbonic acid in the blood, ensuring efficient buffering against acidification. The kidneys and lungs work together to maintain the body's pH: the lungs remove CO2 quickly but in limited capacity, whereas the kidneys have a larger capacity but act more slowly.