Animal Physiology Test Bank Chapter 29 PDF

Test Bank to accompany Animal Physiology, Fourth Edition Hill Wyse Anderson Chapter 29: Kidneys and Excretion (with Notes on Nitrogen Excretion) TEST BANK QUESTIONS Multiple C...

Test Bank to accompany Animal Physiology, Fourth Edition Hill Wyse Anderson Chapter 29: Kidneys and Excretion (with Notes on Nitrogen Excretion) TEST BANK QUESTIONS Multiple Choice 1. Which statement about the kidneys is false? a. They produce and eliminate aqueous solutions derived from the blood plasma. b. They produce and eliminate watery solutions derived from the extracellular fluid. c. They excrete solutes dissolved in water. d. They produce urine that contains high levels of creatinine, which is a direct product of lipid metabolism. Answer: d Textbook Reference: Introduction Bloom’s Category: 2. Understanding 2. Which substance is typically found in urine at the highest concentration? a. Sodium originated from plasma b. Sodium generated from extracellular fluid c. Urea generated from protein metabolism d. Phosphate generated from energy production Answer: c Textbook Reference: Introduction Bloom’s Category: 3. Applying 3. Which of the following would not be found in urine produced by healthy kidneys? a. Potassium b. Proteins c. Phosphate d. Creatinine Answer: b Textbook Reference: Introduction Bloom’s Category: 2. Understanding 4. After the kidneys, the _______ contribute(s) most to filtration. a. lungs b. liver c. heart d. spleen Answer: c © 2016 Sinauer Associates, Inc. Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 4. Analyzing 5. Podocytes are found in the a. glomerulus. b. Bowman’s capsule. c. renal corpuscle. d. glomerulus and the renal corpuscle. Answer: b Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 6. A molecule greater than _______ kilodaltons cannot pass through the nephrons. a. 6.5 b. 9 c. 9.5 d. 12.5 Answer: d Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 1. Remembering 7. Which statement about amphibian nephrons is false? a. Nephrons start at Bowman’s capsule. b. Filtration occurs in the nephrons. c. Nephron walls consist of a single layer of epithelia. d. The loops of Henle are a few mm in length. Answer: d Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 8. Filtration slits are found in a. the glomerulus. b. Bowman’s capsule. c. the renal corpuscle. d. both the glomerulus and the renal corpuscle. Answer: b Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 9. Glomerular filtration rate in vertebrates is defined as the rate of _______ of an animal’s kidney tubules. a. secondary urine formation by all b. secondary urine formation by one c. primary urine formation by all d. primary urine formation by one Answer: c © 2016 Sinauer Associates, Inc. Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 10. If the blood pressure in the glomerular capillary is +5 kPa, the colloid osmotic pressure is –2.5 kPa, and the capsular fluid hydrostatic pressure is –2 kPa, then the filtration pressure is _______ kPa. a. 0.5 b. 4.5 c. 5.0 d. 5.5 Answer: a Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 3. Applying 11. If the filtration pressure is +7 kPa, the colloid osmotic pressure is –3 kPa, and the capsular fluid hydrostatic pressure is –2 kPa, then the blood pressure in the glomerular capillaries is _______ kPa. a. 2 b. 3 c. 8 d. 12 Answer: d Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 3. Applying 12. If the blood pressure in the glomerular capillary is +10 kPa, the filtration pressure is +6 kPa, and the capsular fluid hydrostatic pressure is –2 kPa, then the colloid osmotic pressure is _______ kPa. a. –2 b. –4 c. 2 d. 4 Answer: a Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 3. Applying 13. If the blood pressure in the glomerular capillary is +14 kPa, the filtration pressure is +8 kPa, and the colloid osmotic pressure is –4 kPa, then the capsular fluid hydrostatic pressure is _______ kPa. a. –2 b. –4 c. 4 d. 10 Answer: a Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 3. Applying © 2016 Sinauer Associates, Inc. 14. The _______ system(s) effect(s) the change in flow resistance in the glomerular blood pressure. a. nervous b. endocrine c. digestive d. nervous and endocrine Answer: d Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 15. In amphibians, the first part of the nephron is a. the proximal convoluted tubule. b. Bowman’s capsule. c. the Loop of Henle. d. the collecting duct. Answer: b Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 16. The last part of the nephron in amphibians is a. Bowman’s capsule. b. the Loop of Henle. c. the distal convoluted tubule. d. the collecting duct. Answer: d Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 17. The filtered fluid that forms in the nephrons will first empty into the a. urethra. b. bladder. c. ureter. d. distal convoluted tubule. Answer: c Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 18. In the proximal convoluted tubules of the nephrons of amphibians, sodium is reabsorbed via a. passive transport. b. active transport. c. simple diffusion. d. active transport and passive transport. Answer: b Textbook Reference: Urine Formation in Amphibians © 2016 Sinauer Associates, Inc. Bloom’s Category: 1. Remembering 19. Which substance(s) may be found in the proximal convoluted tubule in the nephrons of amphibians? a. Sodium b. Sodium and chloride c. Glucose d. Sodium, glucose, and chloride Answer: d Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 20. In the nephrons of amphibians, glucose in the proximal convoluted tubule returns to the blood by a. simple diffusion. b. facilitated diffusion. c. primary active transport. d. secondary active transport. Answer: d Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 21. Which values reflect the expected glucose concentrations (in mM) in micropuncture samples collected from the nephron in the following order: Bowman’s capsule, beginning of proximal convoluted tubule, intermediate segment, middle of distal convoluted tubule, and beginning of collecting duct? a. 0; 1; 2; 3; 2 b. 2; 2; 0; 0; 0 c. 0; 0; 0; 0; 0 d. 2; 2; 2; 0; 0 Answer: b Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 3. Applying 22. Which values reflect the expected amino acid concentrations (in mM) in micropuncture samples collected from the nephron in the following order: Bowman’s capsule, beginning of proximal convoluted tubule, intermediate segment, middle of distal convoluted tubule, and beginning of collecting duct? a. 0; 1; 2; 4; 2 b. 0; 0; 0; 0; 0 c. 1; 1; 0; 0; 0 d. 2; 2; 1; 0; 0 Answer: c Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 3. Applying © 2016 Sinauer Associates, Inc. 23. Which values reflect the expected albumen concentrations (in mM) in micropuncture samples collected from the nephron in the following order: Bowman’s capsule, beginning of proximal convoluted tubule, intermediate segment, middle of distal convoluted tubule, and beginning of collecting duct? a. 0; 0; 0; 0; 0 b. 0; 1; 2; 4; 2 c. 1; 1; 0; 0; 0 d. 2; 2; 1; 0; 0 Answer: a Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 3. Applying 24. ADH is released from the a. anterior pituitary. b. posterior pituitary. c. kidneys. d. hypothalamus. Answer: b Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 25. If you inject a known diuretic into a frog, the volume of its a. urine will increase. b. urine will decrease. c. plasma will increase. d. plasma will remain the same. Answer: a Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 4. Analyzing 26. In amphibians, ADH acts on which segment of the nephron to increase reabsorption? a. Proximal convoluted tubule b. Distal convoluted tubule c. Ascending loop of Henle d. Descending loop of Henle Answer: b Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 27. Injection of an ADH inhibitor into a frog causes _______ at the distal convoluted tubule than would occur without such an injection. a. reabsorption of more waste b. secretion of more sodium c. reabsorption of less water d. secretion of less water Answer: c © 2016 Sinauer Associates, Inc. Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 3. Applying 28. If an ADH blocker is administered to an amphibian, the volume of the urine will _______ and the volume of the blood will _______. a. increase; increase b. decrease; increase c. increase; decrease d. remain the same; increase Answer: c Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 3. Applying 29. Administering a substance that enhances the release of ADH to a frog will cause the distal convoluted tubule to a. reabsorb more water than normal. b. reabsorb less water than normal. c. secrete less water than normal. d. secrete more sodium than normal. Answer: a Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 3. Applying 30. In mammals, the length of the loop of Henle in nephrons is correlated with the a. size of the kidney. b. thickness of the renal medulla. c. thickness of the renal pelvis. d. length of the renal cortex. Answer: b Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering 31. In mammals, the nonurea solutes are trapped in the collecting duct because the collecting duct is a. permeable to both water and nonurea solutes. b. impermeable to both water and nonurea solutes. c. impermeable to nonurea solutes but permeable to water. d. permeable to nonurea solutes but impermeable to water. Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 2. Understanding 32. In mammals, the medullary interstitial fluid is _______ to the fluid in the collecting duct. a. hyperosmotic b. isosmotic © 2016 Sinauer Associates, Inc. c. hyposmotic d. isoionic and hyposmotic Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 33. The wall of the ascending limb of the loop of Henle is impermeable to a. sodium. b. potassium. c. chloride. d. water. Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering 34. A direct effect of the active transport of NaCl in the ascending limb of the loop of Henle is that the fluid in the _______ becomes _______. a. lumen; hyposmotic b. lumen; hyperosmotic c. interstitial fluid; hyperosmotic d. interstitial fluid; isosmotic Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 35. During active transport of NaCl in the ascending limb of the loop of Henle, the concentration of NaCl in the lumen a. increases. b. decreases. c. stays the same. d. decreases at first and then increases. Answer: b Textbook Reference: Urine Formation in Mammals Bloom’s Category: 2. Understanding 36. During active transport of NaCl in the ascending limb of the loop of Henle, the concentration of NaCl in the interstitial fluid a. increases. b. decreases. c. stays the same. d. decreases at first and then increases. Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering 37. In the collecting duct, urea reabsorption is mediated by © 2016 Sinauer Associates, Inc. a. the lipid portion of the plasma membrane. b. antiport proteins. c. symport proteins that are regulated by aldosterone. d. protein transporters. Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering 38. Do ATP blockers directly affect urea reabsorption in the collecting duct? a. Yes, urea reabsorption depends on active transport via protein pumps. b. Yes, urea reabsorption depends on active transport via protein transporters. c. No, urea reabsorption is facilitated by protein pumps. d. No, urea reabsorption is facilitated by protein channels. Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 39. If the urea concentration in the interstitial fluid around the collecting duct is increased, urea reabsorption will a. continue because it depends on active transport. b. continue because it depends on passive transport. c. cease because it depends on active transport. d. cease, because reabsorption depends on passive transport. Instead, urea secretion will occur. Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 40. Which statement about urea processing in the nephron is true? a. More urea is excreted than filtered, and some of the urea that gets reabsorbed accumulates in the medulla. b. More urea is reabsorbed than excreted, and some of the urea gets filtered. c. More urea is filtered than reabsorbed, and all of the urea gets excreted. d. More urea is filtered than excreted, and some of the urea that gets reabsorbed accumulates in the medulla. Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 2. Understanding 41. If a drug that blocks Na–K–2Cl cotransporters is administered, blood pressure will _______ and plasma sodium concentration will _______. a. increase; increase b. decrease; increase c. decrease; decrease d. increase; decrease Answer: c © 2016 Sinauer Associates, Inc. Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 42. If a person in antidiuresis produces urine with a concentration of 1200 mOsm, his plasma osmolarity is about _______ mOsm. a. 1200 b. 600 c. 300 d. 2400 Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 43. If a person in diuresis produces urine with a concentration of 50 mOsm, her plasma osmolarity is about _______ mOsm. a. 250 b. 500 c. 600 d. 50 Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 44. ADH acts specifically on the _______ by _______. a. collecting duct; removing aquaporin channels from the membrane. b. collecting duct; inserting aquaporin channels into the membrane. c. loop of Henle; removing aquaporin channels from the membrane. d. loop of Henle; inserting aquaporin channels into the membrane. Answer: b Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering 45. The Na–K–2Cl cotransporter in the nephron is located on the a. apical side and is electroneutral. b. apical side and has a net charge of +1. c. basolateral side and is electroneutral. d. basolateral side and has a net charge of +1. Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 46. If a new protein, aptly named Na–2K–Cl cotransporter, is introduced to the apical side of the nephron in mammals, which of the following statements about this protein would be true? a. The protein has a net charge of +1. b. The protein has a net charge of +2. © 2016 Sinauer Associates, Inc. c. The protein has a net charge of –1. d. The protein has a net charge of –2. Answer: b Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 47.–51. Refer to the figure below. 47. Where is K+ most likely to be secreted into the tubular fluid? a. II b. III c. IV d. V Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 48. Where is most of the glucose reabsorbed from the tubular fluid? a. I © 2016 Sinauer Associates, Inc. b. II c. III d. IV Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 49. During moderate diuresis, what is the most likely osmotic pressure in the tubular fluid at V? a. 300 mOsm b. 600 mOsm c. 75 mOsm d. 5 mOsm Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 50. Where would amino acids be found in the tubular fluid? a. I b. I and II c. I, II, and III d. At all areas in the tubule Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 51. Where would sodium be moving across the apical membranes of the cells lining the tubules? a. I b. I and II c. I, II, and III d. At all areas in the tubule Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 52.–56. Refer to the figure below. © 2016 Sinauer Associates, Inc. 52. What portion of the kidney tubule does the diagram represent? a. Proximal convoluted tubule b. Descending loop of Henle c. Ascending loop of Henle d. Collecting duct Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 53. At which numeral is sodium moving across the membrane? a. I b. I and II c. I, II, and III d. I, II, and IV Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 54. Which process or processes are using the sodium gradient to bring substances into the cell? a. I b. I and II c. I, II, and III d. I, II, and IV Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying © 2016 Sinauer Associates, Inc. 55. Where is secondary active transport of glucose represented? a. I b. II c. III d. IV Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 56. Which numeral represents a transporter that could change the pH of the inside of the cell? a. I b. I and II c. II and III d. II and IV Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 57. Which organisms have loopless nephrons? a. Some birds b. Nonavian reptiles c. Some birds and all amphibians d. Some birds and all nonavian reptiles Answer: d Textbook Reference: Urine Formation in Other Vertebrates Bloom’s Category: 1. Remembering 58. Coelomosacs are found in a. birds. b. crustaceans. c. marine fish. d. amphibians. Answer: b Textbook Reference: Urine Formation in Decapod Crustaceans Bloom’s Category: 1. Remembering 59. In insects, KCl is a. secreted passively. b. secreted actively. c. absorbed passively. d. absorbed actively. Answer: b Textbook Reference: Urine Formation in Insects Bloom’s Category: 1. Remembering © 2016 Sinauer Associates, Inc. 60. The principal waste product in ureotelic animals is a. uric acid. b. urea. c. ammonia. d. ammonium. Answer: b Textbook Reference: Nitrogen Disposition and Excretion Bloom’s Category: 1. Remembering Short Answer 1. Kidney structure may vary from one species to another; however, all kidneys serve the same purpose. What are the common elements and functions of the kidney? Answer: All kidneys consist of tubular elements that discharge directly or indirectly to the outside world. They maintain water balance by producing and eliminating aqueous solutions derived from the blood plasma or other extracellular body fluids. Kidneys maintain the homeostasis of various solute concentrations in the plasma and interstitial fluid. Kidneys control the volume of the blood plasma and other extracellular body fluids by controlling excretion of solutes and water. Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 1. Remembering 2. Regulating the glomerular filtration rate (GFR) is very important in animals. Explain how animals adjust their GFR. Answer: The principal way GFR is adjusted is via the regulation of the function of each individual nephron, ultimately influencing the entire kidney average GFR. Regulation is achieved by modulating vasomotor changes in the diameter (and hence flow resistance) of the glomerular afferent capillary. Vasomotor changes of this sort are controlled by the autonomic nervous system and specific circulating hormones. Regulation of GFR in the nephron also occurs by changes in the permeability of the nephron to water or certain solutes. Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 1. Remembering 3. Which solutes are reabsorbed at the proximal convoluted tubules in the nephrons of amphibians and how is each reabsorbed? Answer: Sodium (Na+) and chloride (Cl–) reabsorption occur at the proximal convoluted tubule (PCT). Na+ is actively reabsorbed across the walls of the proximal tubule, whereas Cl– is passively reabsorbed. The epithelial walls of the PCT are permeable to water to facilitate osmosis. Glucose and amino acids are reabsorbed into the cells of the PCT by secondary active transport, driven by the primary active transport of Na+. Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 1. Remembering © 2016 Sinauer Associates, Inc. 4. Using sodium as an example, discuss the differences between concentration and quantity. Answer: Quantity is an absolute measure, whereas concentration is a relative measure (quantity of solute relative to quantity of water). As a general principle, measures of quantity provide the most direct insight into questions of salt and water balance. The concentrations of Na+, Cl–, and water in the tubular fluid remain, on average, unchanged. Yet, the quantities of these substances exiting the proximal tubule are much lower than those entering. Measures of quantity and concentration are informative, although in different ways. For instance, to determine whether an animal is in Na+ balance, you would measure the quantity of Na+ gained per day and the quantity lost per day and compare the values. Concentration is a measure of the proportion of one substance in relation to another. Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 5. Explain how the micropuncture technique is used to study the physiology of the kidney. Answer: The purpose of micropuncture is to monitor the filtrate solute concentration as it travels through the nephron. In micropuncture, fine micropipettes are inserted into individual nephrons at specific points from the Bowman’s capsule to the collecting duct to sample the fluid. Researchers can look at various solutes (e.g., glucose or amino acid concentrations) to assess whether they increase or decrease as they travel along the nephron. Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 2. Understanding 6. Explain, in detail, the functions of ADH in amphibians. Answer: In amphibians, ADH increases the water permeability of parts of the distal convoluted tubule and decreases the glomerular filtration rate. ADH reduces the glomerulus filtration rate by reducing the numbers of actively filtering nephrons, an effect mediated by inducing vasoconstriction in afferent glomerular blood vessels. The decrease in GFR reduces urine production and promotes water retention in the body, thereby complementing the increase in water reabsorption induced by ADH in the distal tubules. ADH has the potential to increase the rate of active NaCl reabsorption from the renal tubules. Overall, ADH promotes water retention because it enhances solute-driven water reabsorption and decreases the solute load of the urine. Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 2. Understanding 7. What are the differences between the countercurrent multiplier and countercurrent exchanger systems? Answer: The countercurrent multiplier is an active system exemplified by sodium reabsorption in the loops of Henle. In this system, metabolic energy is used to transport NaCl out of the ascending limb and induce fluxes of solutes into or out of the fluid streams. The countercurrent exchange is a passive system exemplified by the heat exchangers in the appendages of mammals. In this system, heat follows a temperature © 2016 Sinauer Associates, Inc. gradient, moving from a warmer to a cooler region. This transfer may occur because the expenditure of metabolic energy has caused a temperature gradient, but the transfer of heat, itself, does not require expenditure of more energy. Textbook Reference: Urine Formation in Mammals Bloom’s Category: 2. Understanding 8. Describe the role of ADH in mammalian nephrons. Answer: In mammals, ADH affects the permeability of the collecting-duct epithelium to water. The effect is mediated by aquaporin-2 (AQP-2), a membrane protein that is inserted into and retrieved from the apical cell membranes of the collecting-duct epithelial cells. The presence of ADH stimulates the insertion of AQP-2 molecules into the apical cell membranes, leading to an increase in collecting-duct epithelial permeability. This osmotic exit of water leads to a more concentrated urine. When ADH levels fall, AQP-2 molecules are retrieved from the apical cell membranes, and epithelial permeability to water decreases, leading to a more dilute urine. Textbook Reference: Urine Formation in Mammals Bloom’s Category: 2. Understanding 9. Describe how urine formation differs between freshwater teleosts and marine teleosts. Answer: In freshwater fish, the walls of the distal convoluted tubule are nearly impermeable to water. Thus, as NaCl is reabsorbed and returned to the body fluids, water remains behind in the tubule, and a dilute urine is produced. This is consistent with their need to remove water from their plasma as they are hyperosmotic to their (freshwater) environment. Marine teleost fish commonly lack the distal convoluted tubule; the loss of water via the dilute urine that commonly occurs in distal convoluted tubules would be disadvantageous to marine teleosts because they are hyposmotic to their (seawater) environment. In addition, freshwater teleosts have relatively large numbers of nephrons and well-developed glomeruli; their GFRs are relatively high. In contrast, marine teleosts tend to have relatively few nephrons and small glomeruli; they have low GFRs. Textbook Reference: Urine Formation in Other Vertebrates Bloom’s Category: 2. Understanding 10. Explain how potassium chloride is secreted in insects. Answer: Potassium chloride (KCl) is secreted by the epithelium of a Malpighian tubule from the blood (hemolymph) bathing the tubule into the lumen of the tubule. The K+ secretion occurs by secondary active transport: an H+-ATPase uses ATP to create electrochemical gradients that drive the secondary active transport of K+. The secretion of K+ into a Malpighian tubule is electrogenic, and Cl– accompanies the K+ passively by following the electrical gradient set up by K+ secretion. Thus, KCl requires the use of ATP for secretion. The movement of KCl into the lumen of a Malpighian tubule drives osmotic entry of water, forming primary-urine. Textbook Reference: Urine Formation in Insects Bloom’s Category: 1. Remembering © 2016 Sinauer Associates, Inc. ONLINE QUIZ QUESTIONS 1. What is the largest molecule that can pass through a nephron? a. A molecule that has a molecular weight of 9.5 kilodaltons b. A molecule that has a molecular weight of 12.5 kilodaltons c. A molecule that has a molecular weight of 13.5 kilodaltons d. A molecule that has a molecular weight of 14.5 kilodaltons Answer: a Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 1. Remembering 2. The colloid osmotic pressure is best defined as the a. pressure generated by the contraction of skeletal muscles pushing on the blood vessels. b. osmotic pressure exerted by plasma proteins in the blood vessels. c. pressure generated by the contraction of smooth muscles around the blood vessels. d. pressure difference between the osmotic pressure of the blood plasma and the osmotic pressure of the capsular fluid. Answer: b Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 3. If the blood pressure in the glomerular capillary is +7 kPa, the colloid osmotic pressure is –3 kPa, and the capsular fluid hydrostatic pressure is –2 kPa, then the filtration pressure is _______ kPa. a. 1 b. 2 c. 3 d. 8 Answer: b Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 3. Applying 4. If the filtration pressure is +8 kPa, the colloid osmotic pressure is –2 kPa, and the capsular fluid hydrostatic pressure is –1 kPa, then the pressure in the glomerular capillaries is _______ kPa. a. 2 b. 3 c. 5 d. 11 Answer: d Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 3. Applying 5. Which of the following will not have an effect on the glomerular blood pressure? a. Nervous system innervation of the smooth muscles that surround blood vessels b. Endocrine system hormones acting on skeletal muscles © 2016 Sinauer Associates, Inc. c. An increase in heart rate d. A change in the diameter of the efferent blood vessel Answer: b Textbook Reference: Basic Mechanisms of Kidney Function Bloom’s Category: 2. Understanding 6. In amphibians, sodium reabsorption begins in a. the loop of Henle. b. the proximal convoluted tubule. c. Bowman’s capsule. d. the distal convoluted to tubule. Answer: b Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 7. In amphibians, chloride reabsorption begins in a. the proximal convoluted tubule. b. Bowman’s capsule. c. the loop of Henle. d. the distal convoluted to tubule. Answer: a Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 2. Understanding 8. Which substance(s) can be present in the proximal convoluted tubule in amphibians’ nephrons? a. Sodium b. Amino acids c. Sodium and chloride d. Sodium, chloride, and amino acids Answer: d Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 3. Applying 9. Which hormone controls water regulation in the kidney? a. Cortisol b. ADH c. Oxytocin d. Epinephrine Answer: b Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 1. Remembering 10. In amphibians, when ADH is released, the number of aquaporins in the bladder a. increases. b. decreases. © 2016 Sinauer Associates, Inc. c. and the distal convoluted tubule increases. d. and the distal convoluted tubule decreases. Answer: c Textbook Reference: Urine Formation in Amphibians Bloom’s Category: 2. Understanding 11. Which sequence demonstrates the correct order of the structures of a mammalian nephron from blood to ureter? a. Proximal convoluted tubule; Bowman’s capsule; loop of Henle; distal convoluted tubule b. Bowman’s capsule; loop of Henle; distal convoluted tubule; proximal convoluted tubule c. Bowman’s capsule; proximal convoluted tubule; loop of Henle; distal convoluted tubule d. Distal convoluted tubule; loop of Henle; Proximal convoluted tubule; Bowman’s capsule Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 4. Analyzing 12. The macula densa in mammalian nephrons secrete a. renin. b. aldosterone. c. ADH. d. sodium. Answer: a Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering 13. The active transport of NaCl in the ascending limb of loop of Henle leads to a. hyperosmotic fluid in the lumen. b. hyperosmotic fluid in the interstitial region. c. isosmotic fluid in the lumen. d. hyposmotic fluid in the interstitial region. Answer: b Textbook Reference: Urine Formation in Mammals Bloom’s Category: 5. Evaluating 14. Urea is reabsorbed in the collecting duct by a. simple diffusion. b. facilitated diffusion. c. primary active transport. d. secondary active transport. Answer: b Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering © 2016 Sinauer Associates, Inc. 15. The vasa recta are a. cells in the collecting ducts. b. substances released from the afferent arteriole. c. blood capillaries around loop of Henle in mammals. d. blood capillaries around the proximal convoluted tubules in mammals. Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 2. Understanding 16. Some medications to treat hypertension act on the a. sodium–potassium pumps. b. sodium channels. c. Na–K–2Cl cotransporter. d. Na–Cl cotransporters. Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 2. Understanding 17. In the mammalian proximal convoluted tubule, sodium reabsorption is coupled with a. sodium. b. glucose. c. protons. d. glucose and protons. Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 1. Remembering 18.–20. Refer to the figure below. © 2016 Sinauer Associates, Inc. 18. Which number corresponds to the lowest osmolarity? a. I b. II c. III d. IV Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 19. Which number signifies the area that will not reabsorb water? a. I b. II c. III d. IV Answer: c Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 20. Which area shows the highest variation in osmolarily? a. I b. II c. III © 2016 Sinauer Associates, Inc. d. V Answer: d Textbook Reference: Urine Formation in Mammals Bloom’s Category: 3. Applying 21. Which structure is usually not found in marine teleosts? a. Distal convoluted tubule b. Glomerular capsule c. Proximal convoluted tubule d. Loop of Henle Answer: a Textbook Reference: Urine Formation in Other Vertebrates Bloom’s Category: 1. Remembering 22. Which statement about marine teleosts is true? a. Some species lack glomeruli. b. They are hyperosmotic to seawater. c. They have more nephrons compared to freshwater teleosts. d. They live in a hyposmotic environment. Answer: a Textbook Reference: Urine Formation in Other Vertebrates Bloom’s Category: 2. Understanding 23. Insects have excretory tubules known as a. Malpighian tubules. b. nephridia. c. loopless nephrons. d. coelomosac. Answer: a Textbook Reference: Urine Formation in Insects Bloom’s Category: 1. Remembering © 2016 Sinauer Associates, Inc.