Solved UPSC CDS/OTA Question
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Q · Excretory Systemmedium · 45s
Which segment of the nephron is impermeable to water but actively transports NaCl?
TopicExcretory System
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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The thick ascending limb of the Loop of Henle actively reabsorbs Na⁺, K⁺, and Cl⁻ via the NKCC₂ cotransporter and is impermeable to water, diluting tubular fluid and contributing to medullary hyperosmolarity.
Final Answer: Option C - Thick ascending limb