Explanation:

Kidneys carries out the function in human beings similar to the one in Malpighian tubules perform in cockroaches, flame cells in worms and contractile vacuole in amoeba.
The kidneys are two bean-shaped organs, each about the size of a fist. They are located just below the rib cage, one on each side of the spine. Every day, the two kidneys filter about 120 to 150 quarts of blood to produce about 1 to 2 quarts of urine, composed of wastes and extra fluid.