question_answer 56)

    The filtration units of kidneys are called (a) ureter                            (b) urethra                          (c) neurons                        (d) nephrons

Answer:

                  (d) Nephrons are the filtration units of kidneys, it is the structural and functional unit of a kidney and has three functions - filtration, reabsorption and secretion. Urine from the kidney passes through a tube called ureter, that carry urine into the urinary bladder. The urethra is a canal that carries urine from bladder and expels it out of body. Neurons are the nerve cells and are functional units of nervous system.