What causes the loop of Henle to establish a concentration gradient in the renal medulla?

💡 Explanation

The high osmolarity in the renal medulla is due to the countercurrent multiplier system, because this mechanism uses the descending and ascending limbs of the loop of Henle to create a concentration gradient. Therefore, the countercurrent multiplier explains the phenomenon, rather than direct diffusion, active glucose transport, or changes in glomerular filtration rate.

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