Which of the following substances is absorbed by passive transport?

Which part of the nephron transports a small amount of urea into the medullary interstitium to maintain the osmolarity?

Indicate whether the following statement is true or false:
Glucose is actively reabsorbed in the proximal convoluted tubule.

Classify the following substances as actively or passively transported during the reabsorption of $GFR$: glucose,amino acids,nitrogenous wastes,$Na^+$,water.

Choose the mismatched part of the nephron with its function.

Studies of selective reabsorption in humans were conducted by: