19 Chapter Multiple Choice

CH 19 11) Kidneys compensate for changes in plasma volume and osmolarity by adjusting the rate of water ________. A) reabsorption only B) secretion only C) resorption only D) reabsorption and secretion E) secretion and resorption

CH 19 12) Which of the following mechanisms is NOT important in the maintenance of the osmotic gradient within the proximal tubule that drives water movement? A) cotransport of chloride B) cotransport of amino acids C) cotransport of glucose D) active reabsorption of sodium E) diffusion of urea

CH 19 13) Which of the following accurately describes the thick ascending limb of the loop of Henle? A) permeable to water in the presence of specific hormones B) permeable to water and does NOT contain Na+/K+/Cl- cotransporters C) impermeable to water and does NOT contain Na+/K+/Cl- cotransporters D) impermeable to water and contains Na+/K+/Cl- cotransporters E) permeable to water and contains Na+/K+/Cl- cotransporters

CH 19 14) In the ascending limb of the loop of Henle, the filtrate will always be ________. A) in equilibrium with the the medullary interstitial fluid B) of a lower osmolarity than the medullary interstitial fluid C) a higher osmolarity than the medullary interstitial fluid D) the same osmolarity as the filtrate in the descending limb of the loop of Henle E) a higher osmolarity than the filtrate in the descending limb of the loop of Henle

CH 19 15) The osmotic gradient in the medullary region of the kidneys is established and maintained by which of the following? A) Na+/K+/Cl- cotransporters in the ascending limb of the loop of Henle B) Na+/K+/Cl- cotransporters in the descending limb of the loop of Henle C) efflux of water from the ascending limb of the loop of Henle D) efflux of water from the descending limb of the loop of Henle E) efflux of Na+ from the descending limb of the loop of Henle

CH 19 16) Which of the following comparisons of osmolarity within the kidneys is INCORRECT? A) The fluid in the proximal tubule is iso-osmotic with cortical interstitial fluid. B) Osmolarity of the ascending limb of the loop of Henle is greater than that of the descending limb. C) Osmolarity of the descending limb of the loop of Henle is iso-osmotic with the medullary interstitial fluid. D) The osmolarity of plasma in the vasa recta varies with its location in the renal medulla. E) Osmolarity of fluid in the proximal tubule is greater than the osmolarity of fluid in the end of the loop of Henle as it enters the distal tubule

CH 19 17) A long loop of Henle would result in which of the following? A) a higher osmolarity in the deeper regions of the renal medulla and the ability to produce a more concentrated urine B) a lower osmolarity in the deeper regions of the renal medulla and the ability to produce a more concentrated urine C) a higher osmolarity in the deeper regions of the renal medulla and the ability to produce a more dilute urine D) a lower osmolarity in the deeper regions of the renal medulla and the ability to produce a more dilute urine E) a higher osmolarity in the renal cortex and the ability to produce a more dilute urine

CH 19 18) The hormone-induced increases in water permeability of the distal tubule and collecting ducts is mediated by a(n) ________. A) increase in aquaporin-2 activity B) increase in aquaporin-3 activity C) increase in paracellular permeability D) decrease in "tightness" of tight junctions E) decrease in paracellular permeability

CH 19 19) What keeps the capillaries of the vasa recta from dissipating the medullary osmotic gradient? A) the smooth muscle cells contain Na+/K+/Cl- cotransporters B) the smooth muscle cells are impermeable to water and ions C) the vascular endothelial cells are impermeable to water and ions D) capillary blood enters and exits the medulla at a similar osmolarity E) the vascular endothelial cells contain Na+/K+/Cl- cotransporters

CH 19 20) If nothing else is removed from the filtrate once it reaches the late distal tubules, the urine excreted would have which of the following properties? A) devoid of ions and large volume B) high osmolarity and low volume C) low osmolarity and low volume D) low osmolarity and large volume E) high osmolarity and large volume

CH 19 21) What solute maintains the medullary interstitial fluid osmotic gradient? A) urea B) sodium ions C) potassium ions D) water E) glucose

CH 19 42) Which of the following is an effect of aldosterone on principal cells? A) decreased number of open Na+ and K+ channels in the basolateral membrane B) decreased number of Na+/K+ pumps in the basolateral membrane C) increased number of open Na+ and K+ channels in the basolateral membrane D) increased number of open Na+ and K+ channels in the apical membrane E) increased number of Na+/K+ pumps in the apical membrane

CH 19 43) Which of the following is associated with actions of aldosterone on principal cells? A) increased sodium secretion B) increased potassium secretion C) decreased blood pressure D) decreased plasma osmolarity E) increased calcium reabsorption

CH 19 44) Renin is released by ________ cells of the ________. A) principal : afferent arteriole B) granular : afferent arteriole C) principal : distal tubule D) granular : distal tubule E) intercalated : afferent arteriole

CH 19 45) What enzyme converts angiotensinogen into angiotensin I. A) Carbonic anhydrase B) Atrial natriuretic peptide C) Angiotensin converting enzyme (ACE) D) Renin E) Mucin

CH 19 46) What enzyme converts angiotensin I into angiotensin II. A) Carbonic anhydrase B) Atrial natriuretic peptide C) Angiotensin converting enzyme (ACE) D) Renin E) Mucin

CH 19 47) Which of the following is NOT one of the functions of angiotensin II? A) vasoconstriction B) stimulate aldosterone secretion C) stimulate antidiuretic hormone (ADH) secretion D) increased thirst E) stimulate renin secretion

CH 19 48) Angiotensin II acts directly in the hypothalamus to stimulate what? A) an increase in thirst B) the release of oxytocin C) an increase in body temperature D) the release of aldosterone E) a systemic increase in blood pressure

CH 19 49) Which of the following conditions is NOT responsible for stimulating the release of renin? A) decreased pressure within the afferent arteriole B) increase in sympathetic nerve activity C) decrease in sodium and chloride in the distal tubule D) increased glomerular filtration rate E) decreased mean arterial pressure

CH 19 50) Angiotensinogen is synthesized by what organ? A) kidney B) bone marrow C) liver D) adrenal gland E) pituitary gland

CH 19 51) What role do the macula densa cells have in controlling renin release? A) They release renin in response to an increase in mean arterial pressure. B) They release renin in response to a decrease in mean arterial pressure. C) They detect changes in the pressure of afferent arterioles, and communicate these changes to juxtaglomerular cells, which secrete renin. D) They detect changes in the pressure of efferent arterioles, and communicate these changes to juxtaglomerular cells, which secrete renin. E) They detect changes in the amount of sodium and chloride in the distal tubules, and communicate these changes to juxtaglomerular cells, which secrete renin.

CH 19 78) Which of the following is NOT one of the effects of changes in pH on the body? A) alterations in protein function B) alterations in central nervous system activity C) alterations in potassium homeostasis D) alteration in water balance E) alterations in cardiac rhythm

CH 19 79) The activity of the respiratory system can increase pH by ________. A) a hyperventilation-induced increase in PCO2 B) a hypoventilation-induced increase in PCO2 C) a hyperventilation-induced decrease in PCO2 D) a hypoventilation-induced decrease in PCO2 E) increasing amount of carbonic acid in the blood

CH 19 80) What is the normal range of blood pH? A) 6.80-7.20 B) 6.90-7.10 C) 6.75-6.95 D) 7.20-7.60 E) 7.35-7.45

CH 19 81) During hyperventilation, why do some people detect a tingling sensation in their hands and feet? A) due to hyperexcitability of afferent neurons B) due to a decrease in blood flow to the distal extremities C) due to a decrease in carbon dioxide in blood D) due to an increase in carbon dioxide in blood E) due to widespread release of catecholamines

CH 19 82) Which of the following is NOT a metabolic disturbance that can result in a metabolic acidosis? A) high protein diet B) high fat diet C) heavy exercise D) excessive vomiting E) severe diarrhea

CH 19 83) What is the most rapid defense against changes in blood pH? A) respiratory compensation B) buffering of hydrogen ions C) renal compensation D) cardiac compensation E) hepatic compensation

CH 19 84) How does severe diarrhea cause a metabolic acidosis? A) production of bicarbonate B) production of hydrogen ions C) loss of hydrogen ions D) loss of phosphate E) loss of bicarbonate

CH 19 85) How does severe vomiting cause a metabolic alkalosis? A) production of bicarbonate B) production of hydrogen ions C) loss of hydrogen ions D) loss of phosphate E) loss of bicarbonate

CH 19 86) Which of the following ions acts as a buffer to minimize changes in intracellular pH? A) phosphate B) bicarbonate C) chloride D) potassium E) sodium

CH 19 87) The role of a buffer is to ________. A) reduce the reabsorption of hydrogen ions in the kidneys B) limit the change in pH with changing hydrogen ion concentrations C) reduce the secretion of hydrogen ions in the kidneys D) reduce the secretion of bicarbonate ions in the kidneys E) enhance the ability of an increase in hydrogen ions to increase pH

CH 19 88) What is the secondary defense against changes in pH that requires minutes to be activated? A) respiratory compensation B) buffering of hydrogen ions C) renal compensation D) cardiac compensation E) hepatic compensation

CH 19 89) Respiratory compensation for changes in pH are originated by ________. A) proprioceptors B) baroreceptors C) central chemoreceptors D) peripheral chemoreceptors E) directly affecting the activity of the diaphragm

CH 19 90) When an increase in hydrogen ions remains after one hour, this will lead to a(n) ________. A) decrease in bicarbonate reabsorption in the kidneys B) increased hydrogen reabsorption in the kidneys C) increase in bicarbonate secretion in the kidneys D) increase in hydrogen ion secretion from the kidneys E) failure of the kidneys to filter any more hydrogen ions

CH 19 91) Which of the following is an effect of the transporters in the proximal tubules? A) secretion of urea B) secretion of potassium C) reabsorption of hydrogen D) secretion of sodium E) reabsorption of bicarbonate

CH 19 92) In the basolateral membrane of proximal tubular cells, bicarbonate is moved out of the cells by ________. A) K+/HCO3- countertransporters only B) HCO3-/Cl- countertransporters only C) Na+/HCO3- cotransporters only D) both K+ HCO3- and HCO3- /CI- countertransporters E) both HCO3- /CI- countertransporters and Na+ / HCO3- cotransporters

CH 19 93) In the proximal tubule, hydrogen ions are transported into the filtrate by ________. A) Na+/H+ countertransporters only B) H+ primary active transporters only C) H+/Cl- cotransporters only D) both Na+/H+ countertransporters and H+ primary active transporters E) both Na+/H+ countertransporters and H+/Cl- cotransporters

CH 19 94) Bicarbonate crosses the apical membrane of the proximal tubule by ________. A) HCO3-/Cl- countertransporters B) Na+/HCO3- cotransporters C) conversion to carbon dioxide D) HCO3- active transporters E) Na+/HCO3- countertransporters

CH 19 95) Which of the following transporters is NOT found embedded in the membrane of the intercalated cells of the late distal tubule and collecting ducts? A) HCO3-/Cl- countertransporters in the basolateral membrane B) Na+/HCO3- cotransporters in the basolateral membrane C) chloride channels in the basolateral membrane D) H+ pumps in the apical membrane E) K+/H+ countertransporters in the apical membrane

CH 19 96) What is the normal source of the new bicarbonate in the late distal tubule and collecting ducts? A) carbon monoxide produced in the distal tubule B) catabolism of lysine C) catabolism of glutamine D) carbon dioxide from the system circulation E) carbon dioxide produced by the tubule cells

CH 19 97) Under severe acidic conditions, the proximal tubules can convert ________ into bicarbonate. A) glutamate B) carbon monoxide C) lysine D) glutamine E) glycine

CH 19 98) Hydrogen ions in the filtrate within the collecting ducts are buffered by the presence of ________. A) phosphate B) bicarbonate C) carbon dioxide D) glutamine E) proteins

CH 19 99) In order to compensate for a hyperventilation, the ________. A) kidneys decrease the reabsorption of bicarbonate B) kidneys increase the conversion of glutamine to bicarbonate C) kidneys increase the secretion of hydrogen ions D) lungs increase ventilation rate E) kidneys increase the reabsorption of hydrogen ions

CH 19 100) Which of the following is NOT a compensation that would occur in response to a metabolic acidosis? A) increased excretion of hydrogen ions B) increased ventilation C) decreased tidal volume D) increased bicarbonate production E) increased conversion of glutamine to bicarbonate

CH 19 101) A patient is exhibiting several signs of acid-base imbalance. Blood tests reveal that blood pH is 7.3, and bicarbonate and carbon dioxide levels in blood are both low. What is the state of this patient? A) metabolic acidosis with respiratory compensation B) respiratory acidosis with renal compensation C) metabolic alkalosis with respiratory compensation D) respiratory alkalosis with renal compensation E) blood pH is normal

CH 19 102) A patient is exhibiting several signs of acid-base imbalance. Blood tests reveal that blood pH is 7.5, and bicarbonate and carbon dioxide levels in blood are both low. What is the state of this patient? A) metabolic acidosis with respiratory compensation B) respiratory acidosis with renal compensation C) metabolic alkalosis with respiratory compensation D) respiratory alkalosis with renal compensation E) blood pH is normal

CH 18 1) Which of the following is NOT a function of the kidneys? A) regulation of plasma ionic concentration B) regulation of plasma osmolarity C) regulation of plasma temperature D) regulation of plasma volume E) regulation of plasma hydrogen concentration

CH 18 2) The primary function of the kidneys involves regulating the ________ and the ________ of plasma and interstitial fluid. A) volume : temperature B) volume : composition C) temperature : composition D) pressure : volume E) composition : osmolarity

CH 18 3) Once produced, urine travels through the ________ until it reaches the bladder, from which it is released into the external environment through the ________. A) ureter : urethra B) urethra : ureter C) collecting duct : ureter D) collecting duct : urethra E) renal hilus : ureter

CH 18 4) Which of the following is NOT part of the urinary system? A) kidneys B) liver C) ureters D) urethra E) bladder

CH 18 5) Despite being less than 1% of body weight, the kidneys receive what percent of resting cardiac output? A) 1% B) 5% C) 15% D) 20% E) 35%

CH 18 6) What are the conical sections of the renal medulla called? A) renal cortex B) renal pelvis C) renal pyramids D) minor calyces E) major calyces

CH 18 7) Where do the collecting ducts of the renal tubules drain? A) ureters B) minor calyces C) major calyces D) renal pelvis E) glomerulus

CH 18 8) What is the functional unit of the kidney? A) loop of Henle B) proximal tubule C) collecting ducts D) nephron E) glomerulus

CH 18 9) What two structures make up the renal corpuscle? A) afferent and efferent arterioles B) major and minor calyces C) nephron and collecting duct D) Bowman's capsule and glomerulus E) proximal straight and proximal convoluted tubules

CH 18 10) Blood leaves the ________ and enters the glomerulus. A) afferent arteriole B) efferent arteriole C) peritubular capillary D) vasa recta E) Bowman's capsule

CH 18 11) Where does blood leaving the glomerulus go to next? A) afferent arteriole B) efferent arteriole C) peritubular capillary D) vasa recta E) Bowman's capsule

CH 18 12) After fluid passes through the entire proximal tubule, the fluid will enter the ________. A) loop of Henle B) distal tubule C) connecting tubule D) collecting duct E) Bowman's capsule

CH 18 13) What type of nephrons are located within the outer region of the kidney and comprise nearly 80% of the nephrons? A) peritubular B) medullary C) juxtaglomerular D) juxtamedullary E) cortical

CH 18 14) The juxtaglomerular apparatus describes the unique region of the nephron where ________. A) the efferent arteriole is in contact with the distal tubule B) the afferent arteriole is in contact with the distal tubule C) the afferent and efferent arterioles are in contact with the distal tubule D) the afferent arteriole is in contact with the proximal tubule E) the afferent and efferent arterioles are in contact with the proximal tubule

CH 18 15) What capillaries come off of the efferent arterioles associated with cortical nephrons? A) glomerulus B) peritubular C) vasa recta D) arcuate E) lobular

CH 18 16) What capillaries come off of the efferent arterioles associated with juxtamedullary nephrons? A) glomerulus B) peritubular C) vasa recta D) arcuate E) lobular

CH 18 17) Which of the following is the correct order of blood supply to the kidneys? A) renal artery interlobar arteries arcuate arteries segmental arteries interlobular arteries efferent arteriole glomerulus afferent arteriole B) renal artery segmental arteries interlobar arteries arcuate arteries interlobular arteries afferent arteriole glomerulus efferent arteriole C) renal artery arcuate arteries interlobular arteries segmental arteries afferent arteriole glomerulus efferent arteriole interlobar arteries D) renal artery segmental arteries interlobular arteries arcuate arteries interlobar arteries efferent arteriole glomerulus afferent arteriole E) renal artery interlobar arteries interlobular arteries arcuate arteries segmental arteries afferent arteriole glomerulus efferent arteriole

CH 18 18) During what renal process are molecules selectively removed from the tubule lumen, moved into the interstitial space, and removed from the kidneys by the peritubular capillaries and the vasa recta? A) filtration B) secretion C) excretion D) reabsorption E) absorption

CH 18 19) The peritubular capillaries and vasa recta drain into hat veins? A) interlobular B) interlobar C) arcuate D) efferent E) segmental

CH 18 20) As fluid moves out of the glomerular capillaries, it passes through gaps in the podocytes called slit pores, whose size is regulated by what? A) fenestrations B) slit diaphragm C) slit muscle D) corpuscle E) glomerular capillary

CH 18 21) What is the process whereby molecules are selectively transported from the peritubular fluid to the lumen of the renal tubules? A) glomerular filtration B) reabsorption C) absorption D) secretion E) excretion

CH 18 22) What is the process whereby protein-free plasma moves by bulk flow from the glomerulus into Bowman's capsules? A) glomerular filtration B) reabsorption C) absorption D) secretion E) excretion

CH 18 23) Which of the following forms the filtration barrier? A) capillary endothelial cells only B) podocytes only C) basement membrane only D) both capillary endothelial cells and basement membrane E) capillary endothelial cells, basement membrane, and podocytes

CH 18 24) What is the sum of Starling's forces within the renal corpuscle called? A) glomerular filtration pressure B) glomerular filtration rate C) glomerular filtration volume D) glomerular oncotic pressure E) glomerular capillary hydrostatic pressure

CH 18 25) What Starling force, which drives fluid out of the glomerulus, is relatively high (~60 mm Hg) due to the resistance of the efferent arterioles. A) Bowman's capsule oncotic B) Glomerular capillary hydrostatic C) Bowman's capsule hydrostatic D) Glomerular oncotic E) Glomerular filtration

CH 18 26) Which of the following pressures across the glomerular capillaries approaches zero? A) glomerular filtration pressure B) glomerular oncotic pressure C) glomerular capillary hydrostatic pressure D) Bowman's capsule oncotic pressure E) Bowman's capsule hydrostatic pressure

CH 18 27) Which of the forces across the glomerular capillaries tends to increase from the afferent to the efferent arteriole ends? A) glomerular filtration pressure B) Bowman's capsule hydrostatic pressure C) Bowman's capsule oncotic pressure D) glomerular capillary hydrostatic pressure E) glomerular oncotic pressure

CH 18 28) Which of the equations below describes the calculation of glomerular filtration pressure (BC = Bowman's capsule and GC = glomerular capillary)? A) (PGC + πBC) - (PBC + πGC) B) (PBC + πBC) - (PGC + πGC) C) (PGC + πGC) - (PBC + πBC) D) (PGC + PBC) - (πGC + πBC) E) (PBC + πGC) - (PGC + πBC)

CH 18 29) Which of the following conditions would increase glomerular filtration pressure? A) decreased resistance of the efferent arterioles B) increased protein in Bowman's space C) increased resistance of the afferent arteriole D) increased protein content in the blood E) increased Bowman's capsule pressure

CH 18 30) Which of the following equations is correct for calculating the filtered load? A) glomerular filtration pressure × plasma concentration of solvent B) glomerular filtration pressure / renal plasma flow C) glomerular filtration rate / renal plasma flow D) glomerular filtration pressure × plasma concentration of solute E) glomerular filtration rate × plasma concentration of solute

CH 18 31) Changes in mean arterial pressure have the potential to alter glomerular filtration rate by directly altering which of the following? A) glomerular oncotic pressure B) glomerular capillary hydrostatic pressure C) Bowman's capsule oncotic pressure D) Bowman's capsule hydrostatic pressure E) efferent arteriole resistance

CH 18 32) What is the normal glomerular filtration rate? A) 125 mL/min B) 625 mL/min C) 3 L/day D) 30 L/day E) 1 gallon/day

CH 18 33) If the glomerular filtration rate is 150 mL/min, renal blood flow is 750 mL/min, and the plasma concentration of solute X is 10 ng/mL, then what is the filtration fraction? A) 10% B) 20% C) 50 ng/min D) 1500 ng/min E) 75 ng/min

CH 18 34) If the glomerular filtration rate is 150 mL/min, renal blood flow is 750 mL/min, and the plasma concentration of solute X is 10 ng/mL, then what is the filtered load of X? A) 10% B) 20% C) 50 ng/min D) 1500 ng/min E) 7500 ng/min

CH 18 35) Which of the following can increase the filtered load of a particular solute? A) increasing the glomerular filtration rate B) increasing the rate of reabsorption C) decreasing the plasma concentration of the solute D) increasing the rate of secretion E) decreasing the rate of excretion

CH 18 36) Over what range of mean arterial pressure does glomerular filtration rate remain stable due to intrinsic regulation? A) 50-150 mm Hg B) 80-180 mm Hg C) 70-110 mm Hg D) 80-100 mm Hg E) 80-120 mm Hg

CH 18 37) During myogenic regulation of glomerular filtration rate, an increase in mean arterial pressure will ________. A) cause the efferent arterioles to constrict and thereby maintain a relatively constant glomerular filtration pressure B) cause the afferent arterioles to constrict and thereby maintain a relatively constant glomerular filtration pressure C) cause the efferent arterioles to dilate and thereby maintain a relatively constant glomerular filtration pressure D) cause the afferent arterioles to dilate and thereby maintain a relatively constant glomerular filtration pressure E) cause the afferent arterioles to dilate and thereby allow glomerular filtration pressure to increase

CH 18 38) In tubuloglomerular feedback, an increase in glomerular filtration rate would increase the ________, thereby stimulating the release of a paracrine factor from the macula densa that would ________. A) afferent arteriolar pressure : constrict the afferent arteriole B) afferent arteriolar pressure : increase filtrate flow C) flow of tubular fluid : dilate the afferent arteriole D) flow of tubular fluid : constrict the efferent arteriole E) flow of tubular fluid : constrict the afferent arteriole

CH 18 39) Contraction of mesangial cells results in a ________, which decreases glomerular filtration. A) decrease in surface area of capillaries available for filtration B) increase in surface area of capillaries available for filtration C) constriction of the afferent arterioles D) dilation of the afferent arterioles E) dilation of the efferent arterioles

CH 18 40) Which of the following is NOT a mechanism whereby glomerular filtration rate is regulated? A) tubuloglomerular feedback B) myogenic regulation C) mesangial cell contraction D) granular cell contraction E) sympathetic nervous system

CH 18 41) A hemorrhage-induced decrease in mean arterial pressure will decrease glomerular filtration rate by intrinsic and extrinsic mechanisms; the extrinsic mechanisms act through ________. A) tubuloglomerular feedback B) the parasympathetic nervous system C) the sympathetic nervous system D) myogenic responses E) mesangial cells

CH 18 42) How does the sympathetic nervous system decrease glomerular filtration rate? A) stimulates constriction of the afferent arteriole only B) stimulates constriction of the efferent arteriole only C) stimulates constriction of both the afferent and efferent arterioles D) stimulates relaxation of the mesangial cells E) stimulates contraction of mesangial cells

CH 18 43) What is the primary barrier to reabsorption in the renal tubules? A) capillary endothelial cell B) tubule epithelial cell C) capillary basement membrane D) tubule basement membrane E) peritubular space

CH 18 44) What condition(s) must exist for a solute to be passively reabsorbed from the renal tubules? A) The solute must be able to permeate the membrane of the tubule epithelial cells, and the solute must be in greater concentration in the plasma than tubule fluid. B) The solute must be able to permeate the membrane of the capillary endothelial cells, and the solute must be in greater concentration in the plasma than tubule fluid. C) The solute must be able to permeate the membrane of the capillary endothelial cells, and the solute must be in greater concentration in the tubule fluid than plasma. D) The solute must be able to permeate the membrane of the tubule epithelial cells, and the solute must be in greater concentration in the tubule fluid than plasma. E) The solute must be able to permeate the membrane of the tubule epithelial cells and capillary endothelial cells. Its concentration is irrelevant.

CH 18 45) Within the kidneys, what membrane has microvillli? A) apical membrane of renal tubule epithelial cells B) basolateral membrane of renal tubule epithelial cells C) basolateral membrane of peritubular capillary endothelial cells D) apical membrane of vasa recta endothelial cells E) glomerulus

CH 18 46) The apical membranes of the tubular epithelial cells contain ________ that increase the surface area for reabsorption. A) mitochondria B) loose junctions C) a basement membrane D) microvilli E) tight junctions

CH 18 47) The diffusion of water across a tubule is driven by differences in ________ across the membrane. A) osmolarity B) partial pressure C) active transport D) volume E) potassium concentration

CH 18 48) When the solute concentration is high enough in the lumen of the renal tubules such that all of the carrier proteins or pumps for that solute are occupied, the system is operating at ________. A) diffusional saturation B) tubular threshold C) renal threshold D) transport maximum E) tubular maximum

CH 18 49) The concentration of glucose in tubular epithelial cells is maintained in an elevated state by what type of transporter on the apical membrane? A) ion channel B) carrier protein C) glucose-linked secondary active transporter D) potassium-linked secondary active transporter E) sodium-linked secondary active transporter

CH 18 50) Which of the following is FALSE concerning glucose transport across the proximal tubule? A) Glucose is normally 100% reabsorbed. B) Glucose is actively transported across the apical membrane by cotransport with sodium. C) Glucose is passively transported across the basolateral membrane by facilitated diffusion. D) Glucose transport requires energy. E) Glucose moves by paracellular transport.

CH 18 51) Which of the following is FALSE concerning renal handling of glucose? A) The maximum rate of glucose reabsorption is 375 mg/min. B) The maximum rate of glucose filtration is 375 mg/min. C) Once glucose concentration in the plasma exceeds the renal threshold, glucose will be excreted in the urine. D) Glucose is completely reabsorbed when its plasma concentration is 100 mg/dL. E) Glucose is actively reabsorbed in the proximal tubule.

CH 18 52) Which of the following substances is NOT secreted at any point into the renal tubules? A) choline B) creatinine C) potassium D) hydrogen E) sodium

CH 18 53) By the time filtrate reaches the loop of Henle, what percentage of the sodium and water has been reabsorbed? A) 1% B) 50% C) 70% D) 90% E) 100%

CH 18 54) By the time the filtrate reaches the loop of Henle, the reabsorption of water and ions has ________. A) left the filtrate iso-osmotic B) left the filtrate hyperosmotic C) left the filtrate hypoosmotic D) removed all of the potassium from the filtrate E) removed all of the sodium from the filtrate

CH 18 55) Which of the following is NOT an accurate description of differences between epithelial cells of the proximal and distal tubules? A) less prominent microvilli in the epithelial cells of the distal tubule B) greater paracellular transport in the epithelial cells of the distal tubule C) fewer mitochondria in the epithelial cells of the distal tubule D) receptors for hormones on the epithelial cells of the distal tubule E) less permeable tight junctions between the epithelial cells of the distal tubule

CH 18 56) In diabetes mellitus, why does polyuria occur? A) a lack of ADH decreases water reabsorption B) a lack of insulin decreases water reabsorption C) hyperglycemia causes increased permeability of the renal tubules to water D) hyperglycemia causes some glucose to remain in the renal tubules which pulls water with it by osmosis E) hypoglycemia causes the excretion of a dilute urine

CH 18 57) What is the brush border? A) the epithelial cells of the renal corpuscle B) microvilli on the apical membrane of Bowman's capsule C) tight junctions between epithelial cells of the loops of Henle D) microvilli on the apical membrane of the proximal tubule E) tight junctions between epithelial cells of the distal tubule

CH 18 58) Most reabsorption occurs in the ________ and is ________. A) proximal tubule : regulated B) proximal tubule : not regulated C) distal tubule and collecting duct : regulated D) distal tubule and collecting duct : not regulated E) loop of Henle : regulated

CH 18 59) Tubular epithelial cells of the collecting duct and distal tubule contain receptors for what hormone that stimulates sodium reabsorption? A) antidiuretic hormone B) renin C) aldosterone D) atrial natriuretic peptide E) erythropoietin

CH 18 60) Tubular epithelial cells of the collecting duct and distal tubule contain receptors for what hormone that stimulates water reabsorption. A) antidiuretic hormone B) renin C) aldosterone D) atrial natriuretic peptide E) erythropoietin

CH 18 61) What creates the osmotic gradient in the renal medulla? A) active transport of solute out of the proximal tubule B) special transport systems of the loops of Henle of juxtamedullary nephrons C) special transport systems of the loops of Henle of cortical nephrons D) active transport of solute out of the distal tubules and collecting ducts E) passive transport of solute out of the distal tubules and collecting ducts

CH 18 62) Substances can enter the renal tubules by what renal processes? A) filtration only B) reabsorption only C) secretion only D) both filtration and secretion E) both reabsorption and secretion

CH 18 63) The amount of a substance excreted from the kidneys is calculated by which of the following equations? A) filtration + secretion + reabsorption B) filtration - secretion - reabsorption C) filtration + secretion - reabsorption D) filtration + (secretion × reabsorption) E) filtration - (secretion × reabsorption)

CH 18 64) Solutes that enter the lumen of the renal tubules are excreted unless they are ________. A) secreted B) reabsorbed C) filtered D) degraded E) bound to receptors

CH 18 65) If the amount of solute excreted per minute is greater than the filtered load, then the NET effect on the solute is ________. A) a combination of reabsorption and secretion in the renal tubules B) an absence of secretion in the renal tubules C) an absence of reabsorption in the renal tubules D) secretion into the renal tubules E) reabsorption from the renal tubules

CH 18 66) Which of the following equations for determining clearance is correct? A) Clearance = filtered load/glomerular filtration rate B) Clearance = filtered load × glomerular filtration rate C) Clearance = excretion rate/plasma concentration D) Clearance = excretion rate × plasma concentration E) Clearance = excretion rate/glomerular filtration rate

CH 18 67) Which of the following equations for determining clearance is correct? A) Clearance = (plasma concentration x urine flow rate) / urine concentration B) Clearance = (urine concentration x urine flow rate) / plasma concentration C) Clearance = plasma concentration / (urine flow rate x urine concentration) D) Clearance = urine concentration / (urine flow rate x plasma concentration) E) Clearance = GRF × urine concentration

CH 18 68) Calculate renal clearance of X given the following information: GFR = 100 mL/min, urine flow rate = 5 mL/min, plasma concentration of X = 10 mg/mL, urine concentration of X = 50 mg/mL. A) 50 mg/min B) 25 mg/min C) 4 mg/min D) 50 mL/min E) 25 mL/min

CH 18 69) Given that GFR is 125 mL/min and the clearance of substance Y is 200 mL/min, which of the following MUST be true of the renal handling of substance Y. A) Y is freely filterable. B) Y is reabsorbed. C) Y is secreted. D) Y is neither reabsorbed nor secreted. E) Y is not freely filtered.

CH 18 70) The clearance of what substance provides the best estimate of glomerular filtration rate? A) sodium B) glucose C) inulin D) creatine E) PAH

CH 18 71) The clearance of what substance provides the best estimate of renal blood flow rate? A) sodium B) glucose C) inulin D) creatine E) PAH

CH 18 72) The clearance of which of the following substances is normally zero? A) sodium B) glucose C) inulin D) creatine E) PAH

CH 18 73) If a substance is neither reabsorbed nor secreted, then its excretion rate is equal to the ________. A) glomerular filtration rate B) filtered load C) glomerular filtration rate D) plasma concentration of the substance E) renal threshold

CH 18 74) What structure is formed by the thickening of the smooth muscle cell wall surrounding the bladder that regulates the flow of urine from the bladder. A) bladder sphincter B) urethral muscle C) detrusor muscle D) internal urethral sphincter E) external urethral sphincter

CH 18 75) How is urine moved through the ureter? A) pressure created within the renal pelvis B) contraction of the internal urethral sphincter C) wavelike contractions of the ureter D) contraction of the detrusor muscle E) contraction of the external urethral sphincter

CH 18 76) Which muscle(s) that regulates micturition is under involuntary control? A) detrusor B) internal urethral sphincter C) external urethral sphincter D) detrusor and the internal urethral sphincter E) detrusor and the external urethral sphincter

CH 18 77) Which of the following occurs during micturition? A) The detrusor muscles relax, muscles of the internal urethral sphincter relax, and muscles of the external urethral sphincter relax. B) The detrusor muscles contract, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter contract. C) The detrusor muscles relax, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter contract. D) The detrusor muscles relax, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter relax. E) The detrusor muscles contract, muscles of the internal urethral sphincter relax, and muscles of the external urethral sphincter relax.

CH 18 78) Stretching of the bladder reflexively causes all of the following EXCEPT ________. A) excitation of parasympathetic neurons, causing the detrusor muscles to contract B) excitation of sympathetic neurons, causing the internal urethral sphincter to relax C) inhibition of somatic neurons to the external urethral sphincter, causing the sphincter to open D) micturition E) opening of the urethral sphincters

CH 18 79) What effect does the sympathetic nervous system have on micturition? A) Sympathetic activity excites muscles of the internal urethral sphincter inhibiting micturition. B) Sympathetic activity inhibits muscles of the internal urethral sphincter inhibiting micturition. C) Sympathetic activity excites muscles of the external urethral sphincter allowing micturition. D) Sympathetic activity inhibits muscles of the external urethral sphincter inhibiting micturition. E) Sympathetic activity excites muscles of the internal urethral sphincter allowing micturition.

CH 18 80) Which of the following is smooth muscle? A) internal urethral sphincter only B) external urethral sphincter only C) detrusor muscle only D) both the internal urethral sphincter and detrusor muscle E) both internal and external urethral sphincters

CH 18 81) To voluntarily control urination, the ________ nervous system innervates the ________. A) somatic : internal urethral sphincter B) somatic : external urethral sphincter C) somatic : detrusor muscle D) autonomic : internal urethral sphincter E) autonomic : external urethral sphincter

CH 18 82) During micturition, neural activity to sphincters or detrusor muscles from which of the following is increased? A) parasympathetic nervous system only B) sympathetic nervous system only C) somatic nervous system only D) both parasympathetic and somatic nervous systems E) both sympathetic and somatic nervous systems

CH 18 83) In older children and adults, the cerebral cortex is able to block micturition by inhibiting nerve activity to the ________. A) detrusor muscle only B) internal urethral sphincter only C) external urethral sphincter only D) detrusor muscle and external urethral sphincter E) internal and external urethral sphincters

CH 18 84) Substance X is freely filtered at the glomerulus. 3 mmole X is filtered, 2 mmole X is reabsorbed, and 2 mmole X is secreted per minute. How much X is excreted per minute? A) 1 mmole B) 2 mmole C) 3 mmole D) 4 mmole E) 5 mmole

CH 18 85) During tubuloglomerular feedback of glomerular filtration rate, paracrines secreted from what structure cause constriction of the afferent arteriole? A) glomerulus B) macula densa C) mesangial cells D) proximal tubule E) juxtaglomerular cells

CH 18 86) In comparison to the distal tubule, the proximal tubule has a ________. A) leakier epithelium and a larger apical surface area B) leakier epithelium and is more responsive to hormones C) tighter epithelium and a larger apical surface area D) tighter epithelium and is more responsive to hormones E) small apical surface area and is more responsive to hormones