Refer to Animation: Countercurrent Multiplication. What would you predict to be the effect on an animal species of having longer loops of Henle in their kidney structure

The correct answers is: I would predict that animals with longer loops of Henle would be able to concentrate their urine more than animals with shorter loops, and thus they would more likely survive in desserts and other dry areas.

Explanation:

The Loop of Henle is a tubule system that connects the proximal convoluted tubule to the distal convoluted tubule in a nephron, the functional and structural unit of the kidney. Its primary job is to establish a concentration gradient in the kidney's medulla by creating a high urea concentration deep in the medulla using a countercurrent multiplier system that uses electrolyte pumps. Through this mechanism, water is reabsorbed to concentrate the urine and impede dehydration.

The length of the loops of Henle is of great importance for the countercurrent multiplier system - the longer they are, the more concentrated the urine can get. Therefore, animals with longer loops can survive better in habitats where there is not much water around.