Deck 18: The Urinary System: Renal Function

Question 1

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, interlobar arteries, interlobular arteries, arcuate arteries, segmental 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, segmental arteries, interlobar arteries, arcuate arteries, interlobular arteries, afferent arteriole, glomerulus, efferent arteriole

Answer 1

E

Question 2

After fluid passes through the entire proximal tubule, the fluid will enter the

A) connecting tubule.
B) collecting duct.
C) loop of Henle.
D) distal tubule.
E) Bowman's capsule.

Answer 2

C

Question 3

What are the conical sections of the renal medulla called?

A) renal pyramids
B) renal cortex
C) minor calyces
D) renal pelvis
E) major calyces

Answer 3

A

Question 4

What is the functional unit of the kidney?

A) loop of Henle
B) nephron
C) glomerulus
D) proximal tubule
E) collecting ducts

Question 5

What hormone is secreted by the kidneys to increase red blood cell synthesis?

A) renin
B) erythropoietin
C) vitamin D
D) angiotensin
E) ANP

Question 6

Where do the collecting ducts of the renal tubules drain?

A) minor calyces
B) major calyces
C) renal pelvis
D) ureters
E) glomerulus

Question 7

What two structures make up the renal corpuscle?

A) afferent and efferent arterioles
B) proximal straight and proximal convoluted tubules
C) Bowman's capsule and glomerulus
D) nephron and collecting duct
E) major and minor calyces

Question 8

Where does blood leaving the glomerulus go next?

A) afferent arteriole
B) Bowman's capsule
C) efferent arteriole
D) peritubular capillary
E) vasa recta

Question 9

What capillaries come off of the efferent arterioles associated with juxtamedullary nephrons?

A) vasa recta
B) arcuate
C) glomerulus
D) peritubular
E) lobular

Question 10

What type of nephron is located within the outer region of the kidney and comprises nearly 80% of the nephrons?

A) medullary
B) cortical
C) juxtaglomerular
D) peritubular
E) juxtamedullary

Question 11

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) glomerular capillary
B) fenestrations
C) corpuscle
D) slit diaphragm
E) slit muscle

Question 12

Blood leaves the

A) afferent arteriole
B) Bowman's capsule
C) peritubular capillary
D) efferent arteriole
E) vasa recta

Question 13

The peritubular capillaries and vasa recta drain into what veins?

A) arcuate
B) segmental
C) interlobular
D) interlobar
E) efferent

Question 14

What capillaries come off of the efferent arterioles associated with cortical nephrons?

A) arcuate
B) glomerulus
C) lobular
D) vasa recta
E) peritubular

Question 15

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) reabsorption
B) excretion
C) absorption
D) filtration
E) secretion

Question 16

Once produced, urine travels through the
released into the external environment through the

A) ureter : urethra
B) urethra : ureter
C) renal hilus : ureter
D) collecting duct : ureter
E) collecting duct : urethra

Question 17

Despite being less than 1% of body weight, the kidneys receive what percent of resting cardiac output?

A) 35%
B) 20%
C) 1%
D) 15%
E) 5%

Question 18

The juxtaglomerular apparatus describes the unique region of the nephron where the

A) afferent arteriole is in contact with the proximal tubule.
B) afferent and efferent arterioles are in contact with the distal tubule.
C) afferent arteriole is in contact with the distal tubule.
D) efferent arteriole is in contact with the distal tubule.
E) afferent and efferent arterioles are in contact with the proximal tubule.

Question 19

The primary function of the kidneys involves regulating the and interstitial fluid.

A) pressure : volume
B) composition : osmolarity
C) volume : composition
D) temperature : composition
E) volume : temperature

Question 20

Which of the following is NOT a function of the kidneys?

A) regulation of plasma ionic concentration
B) regulation of plasma hydrogen concentration
C) regulation of plasma volume
D) regulation of plasma temperature
E) regulation of plasma osmolarity

Question 21

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) glomerular filtration
B) glomerular oncotic
C) Bowman's capsule hydrostatic
D) Bowman's capsule oncotic
E) glomerular capillary hydrostatic

Question 22

What is the process whereby protein -free plasma moves by bulk flow from the glomerulus into Bowman's capsules?

A) glomerular filtration
B) absorption
C) excretion
D) reabsorption
E) secretion

Question 23

Which equation describes the calculation of glomerular filtration pressure (BC = Bowman's capsule and GC = glomerular capillary)?

A) (P_GC + n_BC) -(P_BC + n_GC)
B) (P_BC + n_BC) -(P_GC + n_GC)
C) (P_GC + P_BC) -(n_GC + n_BC)
D) (P_GC + n_GC) -(P_BC + n_BC)
E) (P_BC + n_GC) -(P_GC + n_BC)

Question 24

Over what range of mean arterial pressure does glomerular filtration rate remain stable due to intrinsic regulation?

A) 80 -100 mm Hg
B) 50 -150 mm Hg
C) 80 -180 mm Hg
D) 70 -110 mm Hg
E) 80 -120 mm Hg

Question 25

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) Bowman's capsule oncotic pressure
C) Bowman's capsule hydrostatic pressure
D) efferent arteriole resistance
E) glomerular capillary hydrostatic pressure

Question 26

Which of the forces across the glomerular capillaries tends to increase from the afferent to the efferent arteriole ends?

A) Bowman's capsule oncotic pressure
B) glomerular capillary hydrostatic pressure
C) glomerular filtration pressure
D) glomerular oncotic pressure
E) Bowman's capsule hydrostatic pressure

Question 27

Which of the following conditions would increase glomerular filtration pressure?

A) increased protein in Bowman's space
B) increased resistance of the afferent arteriole
C) decreased resistance of the efferent arterioles
D) increased Bowman's capsule pressure
E) increased protein content in the blood

Question 28

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

Question 29

Which of the following is NOT a mechanism whereby glomerular filtration rate is regulated?

A) mesangial cell contraction
B) granular cell contraction
C) myogenic regulation
D) sympathetic nervous system
E) tubuloglomerular feedback

Question 30

Contraction of mesangial cells results in a(n)

A) constriction of the afferent arterioles , which decreases glomerular filtration.
B) decrease in surface area of capillaries available for filtration
C) increase in surface area of capillaries available for filtration
D) dilation of the efferent arterioles
E) dilation of the afferent arterioles

Question 31

Which of the following can increase the filtered load of a particular solute?

A) increasing the rate of secretion
B) decreasing the rate of excretion
C) increasing the glomerular filtration rate
D) increasing the rate of reabsorption
E) decreasing the plasma concentration of the solute

Question 32

During myogenic regulation of glomerular filtration rate, an increase in mean arterial pressure will cause the

A) afferent arterioles to dilate and thereby maintain a relatively constant glomerular filtration pressure.
B) efferent arterioles to dilate and thereby maintain a relatively constant glomerular filtration pressure.
C) efferent arterioles to constrict and thereby maintain a relatively constant glomerular filtration pressure.
D) afferent arterioles to dilate and thereby allow glomerular filtration pressure to increase.
E) afferent arterioles to constrict and thereby maintain a relatively constant glomerular filtration pressure.

Question 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) 75 ng/min
B) 50 ng/min
C) 20%
D) 1500 ng/min
E) 10%

Question 34

What is the normal glomerular filtration rate?

A) 125 mL/min
B) 625 mL/min
C) 30 L/day
D) 1 gallon/day
E) 3 L/day

Question 35

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) 20%
B) 50 ng/min
C) 1500 ng/min
D) 7500 ng/min
E) 10%

Question 36

Which of the following equations is correct for calculating the filtered load?

A) glomerular filtration rate × plasma concentration of solute
B) glomerular filtration rate / renal plasma flow
C) glomerular filtration pressure × plasma concentration of solvent
D) glomerular filtration pressure / renal plasma flow
E) glomerular filtration pressure × plasma concentration of solute

Question 37

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) flow of tubular fluid : constrict the efferent arteriole
B) afferent arteriolar pressure : constrict the afferent arteriole
C) afferent arteriolar pressure : increase filtrate flow
D) flow of tubular fluid : constrict the afferent arteriole
E) flow of tubular fluid : dilate the afferent arteriole

Question 38

Which of the following pressures across the glomerular capillaries approaches zero?

A) glomerular oncotic pressure
B) Bowman's capsule oncotic pressure
C) glomerular filtration pressure
D) Bowman's capsule hydrostatic pressure
E) glomerular capillary hydrostatic pressure

Question 39

What is the process whereby molecules are selectively transported from the peritubular fluid to the lumen of the renal tubules?

A) reabsorption
B) secretion
C) glomerular filtration
D) absorption
E) excretion

Question 40

What is the sum of Starling's forces within the renal corpuscle called?

A) glomerular capillary hydrostatic pressure
B) glomerular filtration pressure
C) glomerular filtration volume
D) glomerular oncotic pressure
E) glomerular filtration rate

Question 41

Within the kidneys, what membrane has microvilli?

A) apical membrane of renal tubule epithelial cells
B) apical membrane of vasa recta endothelial cells
C) glomerulus
D) basolateral membrane of peritubular capillary endothelial cells
E) basolateral membrane of renal tubule epithelial cells

Question 42

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) fewer mitochondria in the epithelial cells of the distal tubule
C) greater paracellular transport 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

Question 43

Tubular epithelial cells of the collecting duct and distal tubule contain receptors for what hormone that stimulates water reabsorption?

A) atrial natriuretic peptide
B) erythropoietin
C) antidiuretic hormone
D) aldosterone
E) renin

Question 44

Which of the following substances is NOT secreted at any point into the renal tubules?

A) hydrogen
B) creatinine
C) potassium
D) choline
E) sodium

Question 45

What is the brush border?

A) microvilli on the apical membrane of Bowman's capsule
B) tight junctions between epithelial cells of the loops of Henle
C) the epithelial cells of the renal corpuscle
D) microvilli on the apical membrane of the proximal tubule
E) tight junctions between epithelial cells of the distal tubule

Question 46

By the time the filtrate reaches the loop of Henle, the reabsorption of water and ions has

A) left the filtrate hypoosmotic.
B) removed all of the potassium from the filtrate.
C) left the filtrate hyperosmotic.
D) left the filtrate iso -osmotic.
E) removed all of the sodium from the filtrate.

Question 47

In diabetes mellitus, why does polyuria occur?

A) Hypoglycemia causes the excretion of a dilute urine.
B) Hyperglycemia causes increased permeability of the renal tubules to water.
C) A lack of ADH decreases water reabsorption.
D) A lack of insulin decreases water reabsorption.
E) Hyperglycemia causes some glucose to remain in the renal tubules which pulls water with it by osmosis.

Question 48

Which of the following is FALSE concerning renal handling of glucose?

A) The maximum rate of glucose filtration is 375 mg/min.
B) The maximum rate of glucose reabsorption 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 actively reabsorbed in the proximal tubule.
E) Glucose is completely reabsorbed when its plasma concentration is 100 mg/dL.

Question 49

By the time filtrate reaches the loop of Henle, what percentage of the sodium and water has been reabsorbed?

A) 90%
B) 50%
C) 100%
D) 70%
E) 1%

Question 50

The apical membranes of the tubular epithelial cells contain for reabsorption.

A) a basement membrane
B) tight junctions
C) mitochondria
D) microvilli
E) loose junctions

Question 51

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) renal threshold.
B) transport maximum.
C) diffusional saturation.
D) tubular threshold.
E) tubular maximum.

Question 52

Which of the following is FALSE concerning glucose transport across the proximal tubule?

A) Glucose is actively transported across the apical membrane by cotransport with sodium.
B) Glucose is normally 100% reabsorbed.
C) Glucose moves by paracellular transport.
D) Glucose transport requires energy.
E) Glucose is passively transported across the basolateral membrane by facilitated diffusion.

Question 53

What is the primary barrier to reabsorption in the renal tubules?

A) capillary endothelial cell
B) tubule epithelial cell
C) tubule basement membrane
D) capillary basement membrane
E) peritubular space

Question 54

How does the sympathetic nervous system decrease glomerular filtration rate?

A) stimulates contraction of mesangial cells
B) stimulates constriction of the afferent arteriole only
C) stimulates relaxation of the mesangial cells
D) stimulates constriction of both the afferent and efferent arterioles
E) stimulates constriction of the efferent arteriole only

Question 55

Most reabsorption occurs in the

A) proximal tubule : not regulated
B) proximal tubule : regulated and is .
C) distal tubule and collecting duct : not regulated
D) loop of Henle : regulated
E) distal tubule and collecting duct : regulated

Question 56

A hemorrhage -induced decrease in mean arterial pressure will decrease glomerular filtration rate by intrinsic and extrinsic mechanisms; the extrinsic mechanisms act through

A) myogenic responses.
B) the sympathetic nervous system.
C) the parasympathetic nervous system.
D) tubuloglomerular feedback.
E) mesangial cells.

Question 57

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 capillary endothelial 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 tubule epithelial cells and capillary endothelial cells. Its concentration is irrelevant.
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 plasma than tubule fluid.
E) 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.

Question 58

The concentration of glucose in tubular epithelial cells is maintained in an elevated state by what type of transporter on the apical membrane?

A) sodium -linked secondary active transporter
B) potassium -linked secondary active transporter
C) carrier protein
D) ion channel
E) glucose -linked secondary active transporter

Question 59

Tubular epithelial cells of the collecting duct and distal tubule contain receptors for what hormone that stimulates sodium reabsorption?

A) atrial natriuretic peptide
B) erythropoietin
C) renin
D) aldosterone
E) antidiuretic hormone

Question 60

The diffusion of water across a tubule is driven by differences in

A) active transport
B) potassium concentration
C) osmolarity
D) volume
E) partial pressure

Question 61

Solutes that enter the lumen of the renal tubules are excreted unless they are

A) secreted.
B) bound to receptors.
C) degraded.
D) reabsorbed.
E) filtered.

Question 62

Which of the following equations for determining clearance is correct?

A) clearance = urine concentration (plasma concentration × urine flow rate)
B) clearance = (plasma concentration × urine flow rate) / urine concentration
C) clearance = GRF × urine concentration
D) clearance = plasma concentration / (urine concentration × urine flow rate)
E) clearance = (urine concentration × urine flow rate) / plasma concentration

Question 63

The clearance of what substance provides the best estimate of renal blood flow rate?

A) creatine
B) inulin
C) glucose
D) sodium
E) PAH

Question 64

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.

Question 65

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

Question 66

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) 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.

Question 67

Which muscle(s) that regulate(s) micturition is/are under involuntary control?

A) external urethral sphincter
B) detrusor and the external urethral sphincter
C) internal urethral sphincter
D) detrusor and the internal urethral sphincter
E) detrusor

Question 68

How is urine moved through the ureter?

A) wavelike contractions of the ureter
B) pressure created within the renal pelvis
C) contraction of the internal urethral sphincter
D) contraction of the detrusor muscle
E) contraction of the external urethral sphincter

Question 69

What creates the osmotic gradient in the renal medulla?

A) passive transport of solute out of the distal tubules and collecting ducts
B) special transport systems of the loops of Henle of cortical nephrons
C) active transport of solute out of the distal tubules and collecting ducts
D) active transport of solute out of the proximal tubule
E) special transport systems of the loops of Henle of juxtamedullary nephrons

Question 70

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) internal urethral sphincter
D) detrusor muscle
E) external urethral sphincter

Question 71

Stretching of the bladder reflexively causes all of the following EXCEPT

A) excitation of sympathetic neurons, causing the internal urethral sphincter to relax.
B) inhibition of somatic neurons to the external urethral sphincter, causing the sphincter to open.
C) micturition.
D) excitation of parasympathetic neurons, causing the detrusor muscles to contract.
E) opening of the urethral sphincters.

Question 72

The clearance of what substance provides the best estimate of glomerular filtration rate?

A) creatine
B) sodium
C) glucose
D) PAH
E) inulin

Question 73

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

Question 74

Which of the following equations for determining clearance is correct?

A) clearance = filtered load × glomerular filtration rate
B) clearance = excretion rate × plasma concentration
C) clearance = filtered load / glomerular filtration rate
D) clearance = excretion rate / plasma concentration
E) clearance = excretion rate / glomerular filtration rate

Question 75

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)

Question 76

What effect does the sympathetic nervous system have on micturition?

A) Sympathetic activity excites muscles of the internal urethral sphincter allowing micturition.
B) Sympathetic activity excites muscles of the internal urethral sphincter inhibiting micturition.
C) Sympathetic activity inhibits muscles of the internal urethral sphincter inhibiting micturition.
D) Sympathetic activity excites muscles of the external urethral sphincter allowing micturition.
E) Sympathetic activity inhibits muscles of the external urethral sphincter inhibiting micturition.

Question 77

The clearance of which of the following substances is normally zero?

A) inulin
B) sodium
C) glucose
D) PAH
E) creatine

Question 78

If the amount of solute excreted per minute is greater than the filtered load, then the NET effect on the solute is

A) secretion into the renal tubules.
B) an absence of secretion in the renal tubules.
C) reabsorption from the renal tubules.
D) a combination of reabsorption and secretion in the renal tubules.
E) an absence of reabsorption in the renal tubules.

Question 79

If a substance is neither reabsorbed nor secreted, then its excretion rate is equal to the

A) renal threshold.
B) glomerular filtration rate.
C) plasma concentration of the substance.
D) filtered load.

Question 80

Which of the following occurs during micturition?

A) The detrusor muscles relax, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter relax.
B) The detrusor muscles relax, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter contract.
C) The detrusor muscles contract, 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 relax, 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.