5.  This lesson explains how the kidneys handle solutes.  It is remarkable to think that these fist-sized organs process 180 liters of blood per day.  The kidneys are best known for the production of urine.  Many diseases and problems can be found by studying the waste produced by the kidneys.

48. 1.eliminates organic waste products and foreign substances. 2.regulates the volume of the extracellular fluid. 3. maintains plasma ion balance. 4. contributes to homeostatic regulation. 5. does all of the above. 1. The urinary system

49. 2. Functions of the kidneys include all but one of the following. Identify the exception 1.Homeostatic regulation of blood pH 2.Regulation of blood protein levels 3.Maintenance of ion balance in body fluids 4.Regulation of extracellular fluid volume 5.Regulation of blood osmolarity

50. 3. The basic functional unit of the kidney is the 1.renal corpuscle. 2.nephron. 3.filtration unit. 4.glomerulus. 5.loop of Henle.

51. 4. The process of filtration occurs at the 1.collecting duct. 2.distal tubule. 3.loop of Henle. 4.proximal tubule. 5.Bowman's capsule.

52. 5. The process of urine formation involves 1.reabsorption of water. 2.reabsorption of certain solutes. 3.filtration of plasma. 4.secretion of wastes. 5.all of the above.

53. 6. The primary function of the proximal tubule is 1.reabsorption of ions, organic molecules, and vitamins. 2.secretion of drugs. 3.secretion of acids and ammonia. 4.adjusting the urine volume. 5.filtration.

54. 7. Substances secreted by the distal tubule include 1.hydrogen ions. 2.potassium ions. 3.creatinine. 4.all of the above. 5.penicillin.

55. 8. Nancy eats some salty peanuts. What are the responses directly elicited from antidiuretic hormones to decrease plasma osmolarity? 1.Inserts water pores in apical membrane of epithelium of the tubule cells. 2.Increase blood volume 3.Transport Na + out of plasma 4.Insert water pores in the basolateral membrane of the epithelium of the tubule cells 5.All of the above

56. 9. This part of the nephron is permeable to water only in the presence of 1.Descending loop of Henle 2.Ascending loop of Henle 3.Collecting duct 4.Proximal tubule

57. 10. If the clearance of any molecule X that is freely filtered at the glomerulus is less than GFR, then: 1.There is not enough information to answer question. 2.there is net reabsorption of X. 3.X is neither reabsorbed nor secreted. 4.there is net secretion of X.

58. 11. Which of the following describes the balance of a solute in the kidneys? 1.0 = Filtration + Excretion + Reabsorption - Secretion 2.0 = Filtration + Excretion - Reabsorption + Secretion 3.0 = Filtration - Excretion + Reabsorption - Secretion 4.0 = Filtration - Excretion - Reabsorption + Secretion

59. 12. What is the only structure in the nephron in which filtration takes place? 1.Distal tubule 2.Bowman's capsule 3.Loop of Henle 4.Proximal tubule 5.Collecting duct