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Which organ is principally responsible for converting 25‑... | QuestionStock

Representative image for question: Which organ is principally responsible for converting 25‑hydroxyvitamin D into the active 1,25‑dihydroxyvitamin D form via 1α‑hydroxylase?

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Which organ is principally responsible for converting 25‑hydroxyvitamin D into the active 1,25‑dihydroxyvitamin D form via 1α‑hydroxylase?

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Which organ is principally responsible for converting 25‑hydroxyvitamin D into the active 1,25‑dihydroxyvitamin D form via 1α‑hydroxylase?

Options:

Liver
Kidney
Skin
Pancreas

Correct answer: Kidney

Explanation: The renal proximal tubule expresses 1α‑hydroxylase that converts 25(OH)D to active 1,25(OH)2D; this renal activation step is central to calcium homeostasis.

Created 2026-03-10T17:34:16.690Z. Updated 2026-03-10T17:34:16.690Z.