Chapter 51 - Salt and Water Balance and Nitrogen Excretion - 51.5 - The Mammalian Kidney Can Produce Concentrated Urine - 51.5 Recap - Learning Outcomes - Page 1109: 1

The countercurrent multiplier refers to how solutes are concentrated exponentially due to the fluids flowing in opposite directions in the loops of Henle. These loops of Henle work by boosting the osmolarity of the extracellular fluid in the medulla, thus maximizing the rate of diffusion. This is facilitated by the thin cell walls of the descending limb.

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