The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz.
(1) The highest urine osmolality that the human kidney can produce is __________ mOsm/kg. Note: Your response should be a whole number.
(2) At any given level along the descending limb of the loop of Henle, the osmolarity of the fluid in the lumen is __________ the osmolarity of the surrounding interstitial fluid.
(3) The function of the nephron collecting duct is to:
(4) This hormone promotes Na+ conservation, K+ loss, and water reabsorption in the kidney distal tubules.
(5) In the kidneys, molecules reabsorbed from the lumen of the proximal tubule are returned to the circulation via the __________ capillaries.