373 Midterm 2

In response to increased plasma osmolarity, central osmoreceptors would ... Question 8 options: a) expand and increase firing rate. b) shrink and increase firing rate. c) expand and decrease firing rate. d) shrink and decrease firing rate.

b) shrink and increase firing rate.

The vasculature of the mammalian kidney is unusual in that... Question 1 options: a) There are bends in the distal tubules of each nephron looping back toward Bowman's capsule b) Each nephron has glomerular and peritubular capillary beds connected by an efferent arteriole c) It has two capillary beds between the afferent and efferent arteriole of each nephron d) It has ducts that nephrons empty into, which drain into the renal pelvis e) Each nephron has glomerular and peritubular capillary beds connected by a portal vein

b) Each nephron has glomerular and peritubular capillary beds connected by an efferent arteriole

What happens to renal blood flow when the afferent arteriole constricts? Question 2 options: a) It increases b) It decreases c) It stays the same

b) It decreases

Which of the following monitors tubular salt concentrations and can release paracrine factors that affect afferent arteriole diameter? Question 5 options: a) Podocytes around glomerular capillaries b) Macula densa cells c) Glomerular capillaries d) Granular cells e) Proximal tubular epithelial cells

b) Macula densa cells

The ion that is commonly linked to indirect active transport during reabsorption in nephrons is _______. Question 7 options: a) Cl- b) Na+ c) HCO3- d) K+ e) Ca2+

b) Na+

If the clearance rate of X is less than the amount filtered, then ... Question 15 options: a) X is being secreted by the nephron. b) X is being reabsorbed by the nephron. c) X will be rapidly cleared from the blood. d) more X is being secreted than reabsorbed.

b) X is being reabsorbed by the nephron.

Situations that lead to the activation of the RAS pathway include... a) elevated blood pressure in renal afferent arterioles b) an increase in sodium chloride flowing past the macula densa c) increased sympathetic input from the cardiovascular control center in the medulla acting on granular G cells d) a and c e) a, b, c

c) increased sympathetic input from the cardiovascular control center in the medulla acting on granular G cells

If the clearance rate of X is more than the amount filtered, then ... Question 16 options: a) X is being secreted. b) X is being reabsorbed. c) X will be rapidly cleared from the blood. d) both a and c are true

d) both a and c are true

A former house-mate has a genetic disease called diabetes insipidus. His underlying issue is a mutation in the gene that codes for the vasopressin hormone. Which of the following would be true for Kevin? a) he tends to produce very concentrated urine b) his condition could be treated with desmopressin (a vasopressin agonist) c) he tends to produce copious amounts of dilute urine d) a and b e) b and c

e) b and c

In the presence of maximal concentrations of vasopressin and aldosterone, the ascending limb of the loop of Henle... a) increases reabsorption of both water and salt b) increases its reabsorption of salt c) increases its secretion of salt d) continues to reabsorb salt at its usual rate e) continues to secrete salt at its usual rate

e) continues to secrete salt at its usual rate??

In the proximal tubule, bicarbonate ... Question 16 options: a) diffuses across the apical membrane as CO2 and is moved across the basolateral membrane by a transporter. b) diffuses across the basolateral membrane as CO2 and is moved across the apical membrane by a transporter. c) is pumped from the epithelial cell into the interstitium by ATPases. d) is secreted into the filtrate.

a) diffuses across the apical membrane as CO2 and is moved across the basolateral membrane by a transporter.

Severe diarrhea could result in ... Question 20 options: a) metabolic acidosis. b) metabolic alkalosis. c) respiratory acidosis. d) decreased renin secretion. e) decreased vasopressin secretion.

a) metabolic acidosis.

The plasma concentration at which glucose first appears in the urine is called the __________. Question 13 options: a) renal threshold b) sweet spot c) tubuloglomerular capacity d) transport maximum e) saturation point

a) renal threshold

Regulatory responses to correct acid-base imbalances can influence K+ homeostasis due to... a) activity of the H+/K+ ATPase expressed on membranes of the intercalated cells in the distal nephron b) activity of the H+/K+ ATPase expressed on membranes of the intercalated cells in the proximal tubule c) compensatory changes in respiratory rate d) compensatory changes in carbonic anhydrase activity in renal epithelial cells e) A and C

a) activity of the H+/K+ ATPase expressed on membranes of the intercalated cells in the distal nephron

OAT (organic ion transporter) proteins... a) move organic anions from the intersitial fluid into the renal epithelial cell b) move organic anions from the filtrate into the renal epithelial cell c) are symports that co-transport organic anions with dicarboxylates such as a-ketoglutarate d) a and c e) b and c

a) move organic anions from the intersitial fluid into the renal epithelial cell

The final osmolarity of the urine is established ... Question 1 options: a) as it passes through the loop of Henle b) as it passes through the collecting duct c) as it passes through the proximal tubule d) during storage in the bladder e) in the renal pelvis

b) as it passes through the collecting duct

In the presence of maximal concentrations of vasopressin ... Question 4 options: a) most of the water filtered at the glomerulus is reabsorbed in the distal tubule and collecting duct. b) most of the water filtered at the glomerulus is reabsorbed in the proximal tubule. c) urine output is high. d) the collecting duct is completely impermeable to water. e) urine osmolarity is less than 100 mOsM.

b) most of the water filtered at the glomerulus is reabsorbed in the proximal tubule.

The ascending limb of the loop of Henle is permeable to water ... Question 5 options: a) in the presence of vasopressin. b) never c) in the presence of aldosterone. d) always

b) never

Inefficient alveolar ventilation due to lung disease could result in ... Question 19 options: a) respiratory alkalosis. b) respiratory acidosis. c) metabolic acidosis. d) increased reabsorption of H+. e) metabolic alkalosis.

b) respiratory acidosis.

As fluid moves within the tubules through the regions of the nephron, the fluid _______ is most similar in composition to plasma. Question 6 options: a) leaving the collecting duct b) entering the proximal tubule c) leaving the proximal tubule d) leaving the distal tubule e) leaving the ascending limb of the loop of Henle

b) entering the proximal tubule

In a study on renal function in diabetics, creatinine clearance was 120 ml/min and plasma glucose was 320 mg/dL. The transport maximum for glucose is 340 mg/min. What was this person's glucose excretion rate? Question 18 options: a) 220 mg/min b) 240 mg/min c) 44 mg/min d) 44 ml/min e) 9 mg/min

c) 44 mg/min

Your house-mate Matt has a condition called diabetes insipidus. His disease is caused by a loss-of-function mutation in the vasopressin receptor. Which of the following would be true of Matt: Question 3 options: a) He tends to produce a very concentrated urine. b) His condition could be treated with his niece's anti-bedwettting medication, desmopressin. c) He tends to produce copious quantities of very dilute urine. d) a and b e) b and c

c) He tends to produce copious quantities of very dilute urine.

Which of the following is required for formation of the salt gradient in the renal medulla? Question 6 options: a) The ascending limb must transport ions from the interstitium to the tubule. b) The descending limb must transport ions from the interstitium to the tubule. c) The ascending limb must transport ions from the tubule to the interstitium. d) The descending limb must transport ions from the tubule to the interstitium.

c) The ascending limb must transport ions from the tubule to the interstitium.

Considering renal function in the presence of maximal concentrations of aldosterone... a) most of the sodium filtered at the glomerulus is reabsorbed in the distal tubule and collecting duct b) there is increased expression of pumps and channels involved in sodium reabsorption in the proximal tubule c) most of the sodium filtered at the glomerulus is reabsorbed in the proximal tubule d) A and B E) B and C

c) most of the sodium filtered at the glomerulus is reabsorbed in the proximal tubule

Secondary transport is best described as... a) transport of a solute across a membrane against its concentration gradient by an ATPase transporter b) cotransport of two different solutes across a membrane in opposite directions c) transport of a solute across a membrane up or down its gradient by coupling it to the gradient for an ion that was generated/maintained by an ATPase-driven pump d) transport of a solute across a membrane down its gradient by coupling it to the gradient for an ion that was generated/maintained by an ATPase-driven pump e) cotransport of two different solutes across a membrane in the same direction

c) transport of a solute across a membrane up or down its gradient by coupling it to the gradient for an ion that was generated/maintained by an ATPase-driven pump

What part of the nephron tubule is part of the juxtaglomerular apparatus? Question 4 options: a) The descending limb of the loop of Henle where it connects to the ascending limb b) The renal pelvis c) The collecting duct where it joins the ureter d) The ascending limb of the loop of Henle where it connects with the distal tubule e) The proximal tubule where it contacts the descending limb of the loop of Henle

d) The ascending limb of the loop of Henle where it connects with the distal tubule

Which of the following would be a stimulus for aldosterone secretion? Question 9 options: a) Hyperkalemia b) Decreased blood pressure c) Increased blood pressure d) a and b e) a and c

d) a and b

A multi-subunit protein hormone with a molecular weight of 24 kDa could be ... Question 11 options: a) freely filtered at the glomerulus. b) reabsorbed from the renal tubules and recycled back into the circulation to act on target cells again. c) reabsorbed in the proximal tubule, degraded to amino acids by renal epithelial cells and taken into the circulation. d) a and c e) a, b and c

d) a and c

Excretion of significant amounts of protein in the urine ... Question 10 options: a) is most likely due to an issue with glomerular filtration b) is a normal mechanism for clearing the body of excess nitrogenous compounds c) is pathological d) a and c

d) a and c

Glucose reabsorption across the epithelium of the proximal tubule is accomplished by... Question 9 options: a) transport across the apical membrane against its concentration gradient, coupled with Na+ b) transport across the apical membrane down its concentration gradient, coupled with Na+ c) facilitated diffusion across the basolateral membrane down its concentration gradient d) a and c e) b and c

d) a and c

In general, renal compensation for acidosis involves ... Question 15 options: a) secreting protons across the apical membrane into the tubular fluid. b) secreting protons across the basolateral membrane into the interstitium. c) reabsorbing bicarbonate. d) a and c e) b and c

d) a and c

Jasmine has just run her first marathon, in sweltering heat. In the interests of having a fast time, she declined all offers of water at the aid stations. In this self-inflicted state of severe dehydration, which of the following would be elevated? Question 13 options: a) Plasma concentrations of vasopressin b) Plasma concentrations of aldosterone c) Pulse rate d) a and c e) a, b and c

d) a and c

Primary responses to ingestion of a large amount of salt include ... Question 11 options: a) increased vasopressin b) increased aldosterone c) thirst d) a and c e) a, b and c

d) a and c

Renal compensations for perturbations in acid-base balance can disrupt potassium homeostasis because ... Question 18 options: a) a transporter in Type A intercalated cells in the distal nephron involved in compensation for acidosis reabsorbs a K+ for every H+ it secretes b) the hormone aldosterone is released in response to both hyperkalemia and high pH c) a transporter in Type B intercalated cells in the distal nephron involved in compensation for alkalosis secretes a K+ for every H+ it moves into the interstitium d) a and c e) a, b and c

d) a and c

The renal threshold for glucose is 300 mg/100 ml plasma. Your cousin, a type I diabetic, is having trouble regulating her sugar levels. Her plasma glucose is 400 mg/dL. Which of the following would be true: Question 17 options: a) Glucose in her blood would be freely filtered at the glomerulus. b) All the glucose filtered into the renal tubules would be reabsorbed. c) She would be excreting glucose in her urine. d) a and c e) a, b and c

d) a and c

Vasopressin acts on the collecting duct of the nephron to ... Question 2 options: a) increase activity of the Na+/K+ ATPase on the basolateral membrane b) increase expression of ENaC channels on the basolateral surface c) increase salt reabsorption via secondary active transport d) increase water permeability by increasing the number of AQP2 (aquaporin) proteins expressed on the luminal surface e) Both b and d

d) increase water permeability by increasing the number of AQP2 (aquaporin) proteins expressed on the luminal surface

Under normal conditions, the major source of acid in our bodies is derived from ... Question 14 options: a) backwash of acid coming from the stomach b) lactic acid from anaerobic metabolism c) hydrochloric acid, from the combination of H+ and Cl- in plasma d) the conversion of carbon dioxide from aerobic metabolism to bicarbonate and H+ e) the deamination of amino acids

d) the conversion of carbon dioxide from aerobic metabolism to bicarbonate and H+

The renal clearance of a substance X is the ... Question 14 options: a) concentration of X in a sample of urine. b) amount of X cleared from the plasma per unit time. c) excretion rate of X. d) volume of plasma cleared of X per unit time.

d) volume of plasma cleared of X per unit time.

An unusual vascular arrangement found in nephrons includes a) two capillary beds b) a portal vein c) two arterioles d) a and c e) a, b, c

d) a and c

The salt gradient in the renal medulla is important for... a) reabsorption of water from collecting ducts b) reabsorption of water from the proximal tubule c) the ability of vasopressin to regulate water conservation d) a and c e) a, b, c

d) a and c

When your body is dehydrated, water in the urinary bladder will be... a) reabsorbed and returned to the circulation in the presence of certain hormones b) reabsorbed and returned to the circulation after moving back into the kidneys c) reabsorbed and returned to the circulation d) lost from the body via urine

d) lost from the body via urine

Which of the following is TRUE regarding angiotensin II? Question 12 options: a) It stimulates aldosterone release b) It increases vasopressin secretion c) It activates the cardiovascular control center in the medulla d) It is a potent vasoconstrictor e) All of the above

e) All of the above

Which of the following would be a physiological response to a decrease in blood volume? Question 10 options: a) Increased pulse rate b) Vasoconstriction c) Increased thirst d) Conservation of water by the kidneys e) All of the above

e) All of the above

In response to an increase in systemic arterial pressure, you would predict... Question 3 options: a) dilation of afferent arterioles b) constriction of afferent arterioles c) increased GFR d) little or no change in GFR e) Both b and d

e) Both b and d

Inhibition of the NKCC transporter on the apical membrane of epithelial cells lining the ascending loop of Henle would result in ... Question 7 options: a) inhibition of Na+ and Cl- reabsorption. b) disruption of the salt gradient in the renal medulla. c) increased urine production. d) a and c e) a, b and c

e) a, b and c

Na+ moves across the apical membrane of epithelial cells of the proximal tubule via... Question 8 options: a) ENac channels b) symporters that couple amino acid and Na+ transport c) sodium-glucose cotransporters (SGLTs) d) a and c e) a, b and c

e) a, b and c

Renal compensations for alkalosis would include transport of ... Question 17 options: a) H+ into the interstitium by proximal tubule epithelial cells. b) HCO3- into the tubular fluid by Type B intercalated cells in the distal nephron. c) H+ into the interstitium by Type B intercalated cells in the distal nephron. d) a and b e) b and c

e) b and c

Human chorionic gonadotropin (hCG) is a glycoprotein (~36 kDa). Reabsorption of glycoprotein hormones is somewhat inefficient. In a patient with high plasma concentrations of hCG, which of the following is/are true? Question 12 options: a) The kidney is not a major route of elimination of this hormone. b) The hormone would be present in this person's urine. c) The hormone would not be filtered at the glomerulus. d) Amino acids derived from this hormone would be present in this person's circulation. e) b and d

e) b and d