Question: urea is reabsorbed in the nephron loop?
Answer: Urea is freely filtered, 50% are reabsorbed in the proximal tubule with the reabsorption of water (solvent drag). Urea is secreted in the thin ascending limb of Henle loop, so significant amounts of urea reach the distal nephron. In the collecting ducts, urea is reabsorbed together with water.