Final answer:
In addition to secreting hydrogen ions, the body maintains homeostasis by not reabsorbing hydrogen ions back into the blood, with the kidneys playing a critical role through the actions of intercalated cells by adjusting the secretion and absorption of ions like bicarbonate and hydrogen to regulate blood pH.
Step-by-step explanation:
Another way for the body to maintain homeostasis regarding blood pH, in addition to secreting Hydrogen ions into the nephron, is by not reabsorbing Hydrogen ions into the blood (Option A). When the body is too acidic, it can excrete bicarbonate ions to maintain the pH balance. Intercalated cells in the kidneys play a significant role in this process by reabsorbing potassium and bicarbonate ions while secreting hydrogen ions, which directly affects blood's acidity. This allows the plasma's acidity to decrease while the urine becomes more acidic - effectively lowering blood acidity.
Buffers, including proteins, bicarbonate ions, and ammonia, have a large capacity to absorb or release hydrogen ions to protect against pH changes. Alongside kidney function, the lungs can expel excess acid through the exhalation of carbon dioxide, providing a rapid, although limited, response. Together, these mechanisms ensure tight regulation of blood pH levels. By preventing the reabsorption of hydrogen ions, the kidneys help maintain the necessary balance of pH in the blood.