What distinguishes the countercurrent multiplier in juxtamedullary nephrons from that in cortical nephrons during antidiuresis?

💡 Explanation

The countercurrent multiplier is more effective in juxtamedullary nephrons because they have longer loops of Henle that penetrate deeper into the medulla, therefore creating a steeper osmotic gradient. This allows for greater water reabsorption during antidiuresis, rather than relying solely on urea recycling or proximal tubule function.

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