If a patient's renal collecting duct cells become impermeable to water despite normal ADH secretion, which consequence follows?

💡 Explanation

When collecting ducts are impermeable, water cannot be reabsorbed into the medullary interstitium via osmosis; therefore, a larger volume of water remains in the collecting duct and is excreted as urine, rather than being reabsorbed, because aquaporin water channels cannot facilitate water movement.

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