Solved UPSC CDS/OTA Question
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Q · Excretory Systemmedium · 45s
Which process contributes to acid excretion in the kidney?
TopicExcretory System
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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The kidney generates new HCO₃⁻ and excretes H⁺ as ammonium (NH₄⁺) via glutamine metabolism in proximal tubule cells. NH₄⁺ is secreted in exchange for Na⁺ and excreted in urine, aiding acid-base regulation.
Final Answer: Option B - NH₄⁺ production and excretion