Final answer:
NHE and DRA work together to increase the absorption of chloride by excreting bicarbonate, as part of the body's regulation of ion balance. Chloride ions, lost through processes like sweating or vomiting, lead to increased bicarbonate reabsorption by the kidneys.option d is correct answer.
Step-by-step explanation:
NHE and DRA are coupled to increase the absorption of chloride by excreting bicarbonate. This mechanism is a component of the body's intricate regulation of ion balance, specifically concerning the electrolytes in the extracellular fluid (ECF). The Sodium-Hydrogen Exchanger (NHE) and the Chloride/Bicarbonate exchanger (DRA) work together to regulate the absorption and secretion of ions across the renal tubules.
When chloride ions are lost, for example, due to excessive sweating or severe vomiting, the body compensates by increasing the reabsorption of bicarbonate ions by the kidney. This is to maintain a balance of the charges in the body, as chloride ions are crucial for neutralizing positive ion charges. In this context, the body will excrete bicarbonate in place of the lost chloride, leading to an increase in the absorption of chloride.
Aldosterone, a hormone involved in the regulation of the body's sodium and potassium levels, indirectly affects the movement of chloride ions due to their close association with sodium in the ECF. Thus, when aldosterone promotes the reabsorption of sodium, chloride reabsorption is also increased.