Aldosterone stimulates Na+ ______ and K+ ______ in the kidneys.

• A. secretion; secretion
• B. reabsorption; reabsorption
• C. reabsorption; secretion
• D. secretion; reabsorption

Answer: (C)

Verified step by step guidance

1. Understand the role of aldosterone in kidney function: Aldosterone is a hormone that regulates electrolyte balance by acting on the kidney tubules.
2. Recall that aldosterone increases sodium (Na+) reabsorption, meaning it promotes the movement of Na+ from the kidney filtrate back into the bloodstream.
3. Recognize that aldosterone simultaneously increases potassium (K+) secretion, which means it promotes the movement of K+ from the blood into the kidney filtrate to be excreted in urine.
4. Summarize the effects: Aldosterone stimulates Na+ reabsorption and K+ secretion in the kidneys.
5. Match this understanding to the answer choices to select the correct pair: 'reabsorption; secretion'.