The collecting ducts and the loop of Henle are located in the <u>medulla</u> of the kidney.
Explanation:
The kidney consists of the three main regions – outer cortex, middle medulla, and the inner renal pelvis regions.
The main function of filtering and elimination of waste takes place in the medullary regions of the kidney.
Renal medulla is arranged into renal pyramid like structures. The medulla comprises the collecting ducts, loop of Henle, vasa recta and interstitium.
The collecting duct or tubule is a long slender twisting tube which collects the fluid (urine) from the nephrons and transports to the inner renal pelvis region of the kidney.
The loop of Henle is a highly convoluted U-shaped tubule with an ascending and a descending limb. This loop facilitates reabsorption of water and sodium ions necessary for the body from the filtrate formed
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