front 1 A urine dipstick is normal in a healthy adult because the glomerular capillary barrier normally produces filtrate with which composition? A) Protein-rich and cell-free B) Protein-free and cell-free C) Protein-free with erythrocytes D) Protein-rich with erythrocytes | back 1 B. Protein-free and cell-free |
front 2 Glomerular filtrate is normally essentially devoid of red blood cells because glomerular capillaries are relatively impermeable to which components? A) Proteins and cellular elements B) Sodium and chloride ions C) Water and small solutes D) Glucose and amino acids | back 2 A. Proteins and cellular elements |
front 3 A patient has normal plasma calcium, but not all calcium is freely filterable at the glomerulus. Which calcium fraction is not filtered? A) Ionized calcium B) Filtered calcium C) Protein-bound calcium D) Tubular calcium | back 3 C. Protein-bound calcium |
front 4 Most plasma fatty acids are not freely filtered across glomerular capillaries because they are primarily: A) Bound to proteins B) Stored in erythrocytes C) Trapped in podocytes D) Secreted by tubules | back 4 A. Bound to proteins |
front 5 Which two variables directly determine glomerular filtration rate? A) Hematocrit and plasma sodium B) Kf and net filtration pressure C) Tubule length and urine flow D) ADH and bladder pressure | back 5 B. Kf and net filtration pressure |
front 6 The glomerular capillary filtration coefficient, Kf, is the product of which two capillary properties? A) Pressure and plasma protein B) Diameter and blood viscosity C) Permeability and surface area D) Osmolality and renal flow | back 6 C. Permeability and surface area |
front 7 In an average adult, which value best matches normal glomerular filtration rate A) 13 ml/min B) 60 ml/min C) 125 ml/min D) 1100 ml/min | back 7 C. 125 ml/min |
front 8 A normal adult has a GFR of 125 ml/min. Which daily filtration volume does this approximate? A) 3 L/day B) 30 L/day C) 60 L/day D) 180 L/day | back 8 D. 180 L/day |
front 9 Which equation correctly defines filtration fraction? A) Renal plasma flow/GFR B) GFR/renal plasma flow C) GFR/renal blood flow D) Urine flow/GFR | back 9 B. GFR/renal plasma flow |
front 10 A student compares the glomerular capillary membrane with typical systemic capillaries. What structural feature is unique? A) Three major filtration layers B) No basement membrane C) Two endothelial layers D) Complete cellular occlusion | back 10 A. Three major filtration layers |
front 11 Which sequence lists the three major layers of the glomerular capillary membrane from blood outward? A) Podocyte; endothelium; basement membrane B) Basement membrane; podocyte; endothelium C) Endothelium; basement membrane; podocyte D) Endothelium; podocyte; basement membrane | back 11 C. Endothelium; basement membrane; podocyte |
front 12 The outer epithelial cell layer of the glomerular filtration barrier is formed by which cells? A) Mesangial cells B) Podocytes C) Macula densa cells D) Juxtaglomerular cells | back 12 B. Podocytes |
front 13 The glomerular capillary endothelium contains thousands of small holes. What are these openings called? A) Slit pores B) Fenestrae C) Tight junctions D) Canaliculi | back 13 B. Fenestrae |
front 14 The glomerular basement membrane is mainly a meshwork of which substances A) Elastin and fibrinogen B) Albumin and globulin C) Collagen and proteoglycans D) Keratin and myosin | back 14 C. Collagen and proteoglycans |
front 15 Why can large amounts of water and small solutes pass through the glomerular basement membrane? A) It has large mesh spaces B) It lacks negative charge C) It actively pumps water D) It contains red cell pores | back 15 A. It has large mesh spaces |
front 16 Podocyte foot processes are separated by filtration gaps called: A) Fenestrae B) Slit pores C) Major calyces D) Tight junctions | back 16 B. Slit pores |
front 17 Through which structure does filtrate move between podocyte foot processes? A) Fenestrated liver pores B) Macula densa plaques C) Slit pores D) Cortical collecting ducts | back 17 C. Slit pores |
front 18 Which property of glomerular epithelial cells provides additional restriction to plasma protein filtration? A) Positive electrical charge B) Negative electrical charge C) High lipid solubility D) Smooth muscle contraction | back 18 B. Negative electrical charge |
front 19 Despite high filtration rate, the glomerular filtration barrier selectively filters molecules mainly according to: A) Size and electrical charge B) pH and temperature C) Sodium and potassium content D) Hormonal and neural tone | back 19 A. Size and electrical charge |
front 20 A molecule has filterability of 1.0. What does this mean? A) Not filtered at all B) Freely filtered like water C) Half as filtered as water D) Secreted after filtration | back 20 B. Freely filtered like water |
front 21 Albumin is strongly restricted from glomerular filtration primarily because it is large and has which charge? A) Positive B) Neutral C) Negative D) Variable | back 21 C. Negative |
front 22 Why does the negatively charged glomerular wall repel albumin? A) Albumin is positively charged B) Albumin is negatively charged C) Albumin is lipid soluble D) Albumin is bound to calcium | back 22 B. Albumin is negatively charged |
front 23 Which glomerular wall component contributes negative charge that restricts albumin filtration? A) Proteoglycans B) Hemoglobin C) Creatinine D) Bicarbonate | back 23 A. Proteoglycans |
front 24 For dextrans of equal molecular weight, which type is filtered more readily through the glomerular barrier? A) Negatively charged dextran B) Neutral dextran C) Protein-bound dextran D) Albumin-bound dextran | back 24 B. Neutral dextran |
front 25 The negative charges of the basement membrane and podocytes most strongly restrict which molecules? A) Small positively charged ions B) Large negatively charged molecules C) Small neutral solutes D) Water molecules | back 25 B. Large negatively charged molecules |
front 26 A child develops selective albuminuria despite nearly normal kidney histology. Which early barrier abnormality best explains this? A) Loss of negative charges B) Excess slit pore closure C) Increased erythrocyte filtration D) Loss of renal blood flow | back 26 A. Loss of negative charges |
front 27 Loss of negative charges on the glomerular basement membrane before obvious histologic change is characteristic of: A) Nephrotic obstruction B) Minimal change nephropathy C) Acute pyelonephritis D) Renal papillary necrosis | back 27 B. Minimal change nephropathy |
front 28 In minimal change nephropathy, which urinary abnormality occurs because lower molecular weight proteins are filtered? A) Glycosuria B) Hematuria C) Proteinuria or albuminuria D) Ketouria | back 28 C. Proteinuria or albuminuria |
front 29 Which protein is especially likely to appear in urine when glomerular negative charge is lost? A) Albumin B) Fibrinogen C) Hemoglobin D) Myosin | back 29 A. Albumin |
front 30 The term albuminuria most directly refers to which abnormal finding? A) Albumin in urine B) Albumin in plasma C) Albumin in interstitium D) Albumin in cells | back 30 A. Albumin in urine |
front 31 Which pair correctly identifies the two immediate determinants of GFR in the filtration equation? A) Kf and net filtration pressure B) RPF and filtration fraction C) Hematocrit and renal blood flow D) Urine pressure and bladder pressure | back 31 A. Kf and net filtration pressure |
front 32 Which equation correctly describes glomerular filtration rate? A) GFR = Kf/NFP B) GFR = NFP/Kf C) GFR = Kf × NFP D) GFR = RPF × hematocrit | back 32 C. GFR = Kf × NFP |
front 33 Net filtration pressure across glomerular capillaries is the sum of which forces? A) Hydrostatic and colloid osmotic forces B) Electrical and metabolic forces C) Tubular and ureteral pressures D) Neural and hormonal forces | back 33 A. Hydrostatic and colloid osmotic forces |
front 34 Which force favors filtration across the glomerular capillary membrane? A) Bowman hydrostatic pressure B) Glomerular hydrostatic pressure C) Glomerular oncotic pressure D) Plasma protein pressure | back 34 B. Glomerular hydrostatic pressure |
front 35 Which force opposes filtration by pushing fluid back toward glomerular capillaries from Bowman’s capsule? A) Bowman hydrostatic pressure B) Bowman oncotic pressure C) Glomerular hydrostatic pressure D) Interstitial oncotic pressure | back 35 A. Bowman hydrostatic pressure |
front 36 Which force opposes filtration because plasma proteins retain water within glomerular capillaries? A) Bowman hydrostatic pressure B) Bowman oncotic pressure C) Glomerular colloid osmotic pressure D) Glomerular hydrostatic pressure | back 36 C. Glomerular colloid osmotic pressure |
front 37 Which force would promote filtration if proteins were present in Bowman’s capsule? A) Bowman colloid osmotic pressure B) Glomerular colloid osmotic pressure C) Bowman hydrostatic pressure D) Peritubular hydrostatic pressure | back 37 A. Bowman colloid osmotic pressure |
front 38 A patient with ureteral obstruction has increased pressure transmitted backward into Bowman’s capsule. What is the expected direct effect on GFR? A) GFR increases markedly B) GFR remains unchanged C) GFR decreases D) GFR doubles transiently | back 38 C. GFR decreases |
front 39 A patient with uric acid stones obstructing the ureter develops reduced filtration. Which pressure change best explains the lower GFR? A) Increased Bowman hydrostatic pressure B) Decreased plasma oncotic pressure C) Increased afferent hydrostatic pressure D) Decreased renal venous pressure | back 39 A. Increased Bowman hydrostatic pressure |
front 40 Calcium or uric acid precipitates lodge in the ureter and obstruct urinary outflow. Which downstream complication may occur if obstruction persists? A) Nephrotic syndrome B) Hydronephrosis C) Central diabetes insipidus D) Minimal change disease | back 40 B. Hydronephrosis |
front 41 Hydronephrosis from ureteral obstruction is best described as distention and dilation of which structures? A) Cortex and glomeruli B) Renal artery and vein C) Renal pelvis and calyces D) Tubules and vasa recta | back 41 C. Renal pelvis and calyces |
front 42 A patient has an obstructing ureteral stone with persistent elevated Bowman’s capsule pressure. What is the major renal risk if the obstruction is not relieved? A) Increased nephron regeneration B) Permanent kidney damage C) Increased renal oxygen delivery D) Reduced plasma protein filtration | back 42 B. Permanent kidney damage |
front 43 When one-fifth of glomerular capillary fluid filters into Bowman’s capsule, why do remaining plasma proteins become concentrated? A) Proteins are not filtered B) Proteins are actively secreted C) Proteins enter podocyte cytoplasm D) Proteins bind filtered glucose | back 43 A. Proteins are not filtered |
front 44 If glomerular hydrostatic pressure is held constant, increasing blood flow into the glomerulus tends to have which effect on GFR? A) Increases GFR B) Decreases GFR C) Stops filtration D) Causes hydronephrosis | back 44 A. Increases GFR |
front 45 If glomerular hydrostatic pressure is constant but blood flow into the glomerulus falls, which effect on GFR is expected? A) GFR rises sharply B) GFR decreases C) GFR becomes pressure-independent D) GFR equals renal blood flow | back 45 B. GFR decreases |
front 46 Which set contains the three main determinants of glomerular hydrostatic pressure? A) ADH, aldosterone, renin B) Albumin, sodium, chloride C) Arterial pressure, afferent resistance, efferent resistance D) Tubule length, plasma volume, hematocrit | back 46 C. Arterial pressure, afferent resistance, efferent resistance |
front 47 A drug dilates the afferent arteriole without changing other variables. What happens to glomerular hydrostatic pressure and GFR? A) Both decrease B) Pressure decreases; GFR increases C) Pressure increases; GFR decreases D) Both increase | back 47 D. Both increase |
front 48 Afferent arteriolar dilation increases GFR primarily by producing which hemodynamic change? A) Increased glomerular hydrostatic pressure B) Increased Bowman capsule pressure C) Increased glomerular oncotic pressure D) Reduced renal artery pressure | back 48 A. Increased glomerular hydrostatic pressure |
front 49 Afferent arteriolar constriction would be expected to have which effect on glomerular hydrostatic pressure and GFR? A) Both increase B) Both decrease C) Pressure increases; GFR decreases D) Pressure decreases; GFR increases | back 49 B. Both decrease |
front 50 A patient receives a drug that moderately constricts efferent arterioles. Which immediate glomerular pressure change explains the initial GFR effect? A) Increased Bowman pressure B) Reduced glomerular pressure C) Increased glomerular hydrostatic pressure D) Reduced plasma protein pressure | back 50 C. Increased glomerular hydrostatic pressure |
front 51 At moderate levels of efferent arteriolar constriction, what is the usual effect on GFR? A) Slight increase B) Severe decrease C) No possible change D) Complete filtration arrest | back 51 A. Slight increase |
front 52 With severe efferent arteriolar constriction, what happens to GFR? A) Continues increasing indefinitely B) Decreases C) Becomes independent of proteins D) Equals renal plasma flow | back 52 B. Decreases |
front 53 Which pattern best describes GFR as efferent arteriolar constriction progresses from moderate to severe? A) Decrease then increase B) Increase then decrease C) No change then increase D) Continuous linear increase | back 53 B. Increase then decrease |
front 54 Why does severe efferent arteriolar constriction eventually decrease GFR despite raising glomerular hydrostatic pressure? A) Bowman pressure becomes negative B) Plasma proteins disappear from capillaries C) Colloid osmotic pressure rises rapidly D) Afferent arterioles fully dilate | back 54 C. Colloid osmotic pressure rises rapidly |
front 55 During severe efferent constriction, plasma protein concentration increases markedly. Which effect makes colloid osmotic pressure rise nonlinearly? A) Donnan effect B) Starling dilution C) Ureterorenal reflex D) Micturition reflex | back 55 A. Donnan effect |
front 56 In severe efferent arteriolar constriction, why does colloid osmotic pressure rise faster at higher protein concentrations? A) Proteins become freely filtered B) Protein-bound ions add osmotic force C) Bowman capsule secretes albumin D) Vasa recta stop concentrating urine | back 56 B. Protein-bound ions add osmotic force |
front 57 If renal blood flow and GFR decrease, sodium filtration decreases. What happens to sodium reabsorption and renal oxygen consumption? A) Both increase B) Reabsorption increases; oxygen falls C) Reabsorption falls; oxygen rises D) Both decrease | back 57 D. Both decrease |
front 58 Why does reduced GFR lower renal oxygen consumption? A) Less sodium is reabsorbed B) More proteins are filtered C) More glucose is secreted D) Less blood reaches cortex | back 58 A. Less sodium is reabsorbed |
front 59 Which equation correctly represents renal blood flow? A) Resistance ÷ pressure gradient B) Renal vein pressure ÷ resistance C) Pressure gradient ÷ total resistance D) GFR ÷ renal plasma flow | back 59 C. Pressure gradient ÷ total resistance |
front 60 Renal blood flow is calculated using which pressure gradient? A) Bowman minus tubular pressure B) Renal artery minus renal vein C) Glomerular minus Bowman pressure D) Afferent minus efferent pressure | back 60 B. Renal artery minus renal vein |
front 61 In the renal blood flow equation, the pressure gradient is divided by which variable? A) Total renal vascular resistance B) Filtration fraction C) Plasma colloid osmotic pressure D) Glomerular filtration coefficient | back 61 A. Total renal vascular resistance |
front 62 If renal artery and renal vein pressures remain constant, increased renal vascular resistance has what effect on renal blood flow? A) Increases flow B) Decreases flow C) Stops GFR only D) Increases filtration fraction only | back 62 B. Decreases flow |
front 63 If renal artery and renal vein pressures remain constant, decreased renal vascular resistance has what effect on renal blood flow? A) Decreases flow B) Does not affect flow C) Increases flow D) Stops medullary flow | back 63 C. Increases flow |
front 64 Which kidney region receives most renal blood flow? A) Renal cortex B) Renal medulla C) Renal pelvis D) Renal papilla | back 64 A. Renal cortex |
front 65 Blood flow to the renal medulla is supplied by which specialized capillary system A) Glomerular capillaries B) Cortical veins C) Vasa recta D) Afferent arterioles | back 65 C. Vasa recta |
front 66 The vasa recta are best described as a specialized portion of which capillary system? A) Peritubular capillary system B) Glomerular capillary system C) Portal venous system D) Pulmonary capillary system | back 66 A. Peritubular capillary system |
front 67 A patient with severe hemorrhage has intense renal sympathetic nerve activation. What is the expected effect on renal arterioles, renal blood flow, and GFR? A) Vasodilation; increased flow; increased GFR B) Vasoconstriction; decreased flow; decreased GFR C) Vasodilation; decreased flow; increased GFR D) Vasoconstriction; increased flow; decreased GFR | back 67 B. Vasoconstriction; decreased flow; decreased GFR |
front 68 Strong activation of renal sympathetic nerves directly causes which renal vascular response? A) Constriction of renal arterioles B) Dilation of renal arterioles C) Relaxation of efferent venules D) Dilation of vasa recta | back 68 A. Constriction of renal arterioles |
front 69 A patient has a moderate fall in carotid sinus and cardiopulmonary receptor pressure, causing reflex sympathetic activation. What is the usual effect on renal blood flow and GFR? A) Marked increase in both B) Complete loss of autoregulation C) Little influence on both D) Severe decrease in both | back 69 C. Little influence on both |
front 70 Which situation is most likely to substantially decrease renal blood flow and GFR through sympathetic effects? A) Mild baroreceptor unloading B) Moderate cardiopulmonary unloading C) Strong renal nerve activation D) Normal postural adjustment | back 70 C. Strong renal nerve activation |
front 71 Which adrenal medullary hormones constrict both afferent and efferent arterioles, reducing renal blood flow and GFR? A) Aldosterone and cortisol B) Norepinephrine and epinephrine C) Renin and angiotensin II D) ADH and oxytocin | back 71 B. Norepinephrine and epinephrine |
front 72 Which paired renal effect best matches norepinephrine and epinephrine release A) Arteriolar dilation; increased GFR B) Afferent dilation; reduced filtration C) Arteriolar constriction; reduced GFR D) Efferent dilation; increased flow | back 72 C. Arteriolar constriction; reduced GFR |
front 73 Endothelin is best described as which type of renal vascular mediator? A) Vasodilator from podocytes B) Vasoconstrictor from damaged endothelium C) Anticoagulant from collecting ducts D) Natriuretic peptide from macula densa | back 73 B. Vasoconstrictor from damaged endothelium |
front 74 Which mediator can be released by damaged vascular endothelial cells in the kidneys and other tissues? A) Endothelin B) Calcitriol C) Erythropoietin D) Albumin | back 74 A. Endothelin |
front 75 Which mediator is formed both in the kidneys and in the systemic circulation? A) Angiotensin II B) Evans blue dye C) Antipyrine D) 51Cr-labeled erythrocytes | back 75 A. Angiotensin II |
front 76 Nitric oxide and prostaglandins help preserve renal perfusion by counteracting vasoconstrictor effects of which mediator? A) Erythropoietin B) Calcitriol C) Angiotensin II D) Inulin | back 76 C. Angiotensin II |
front 77 Which pair of mediators opposes angiotensin II–mediated vasoconstriction in renal blood vessels? A) ADH and aldosterone B) Nitric oxide and prostaglandins C) Epinephrine and norepinephrine D) Endothelin and renin | back 77 B. Nitric oxide and prostaglandins |
front 78 Increased angiotensin II levels have which combined effect on glomerular hydrostatic pressure and renal blood flow? A) Lower pressure; lower flow B) Lower pressure; higher flow C) Raise pressure; lower flow D) Raise pressure; higher flow | back 78 C. Raise pressure; lower flow |
front 79 Angiotensin II raises glomerular hydrostatic pressure primarily by constricting which vessel? A) Afferent arteriole B) Efferent arteriole C) Interlobular artery D) Cortical vein | back 79 B. Efferent arteriole |
front 80 A patient has elevated angiotensin II during low effective circulating volume. Which effect helps preserve GFR? A) Prevents fall in glomerular pressure B) Increases Bowman capsule pressure C) Dilates efferent arterioles strongly D) Blocks sodium reabsorption | back 80 A. Prevents fall in glomerular pressure |
front 81 Elevated angiotensin II helps prevent decreases in GFR by maintaining which pressure? A) Bowman hydrostatic pressure B) Renal venous pressure C) Glomerular hydrostatic pressure D) Interstitial oncotic pressure | back 81 C. Glomerular hydrostatic pressure |
front 82 Angiotensin II reduces renal blood flow by efferent constriction. What downstream peritubular effect promotes sodium and water retention? A) Increased peritubular flow B) Decreased peritubular flow C) Increased Bowman pressure D) Decreased tubular permeability | back 82 B. Decreased peritubular flow |
front 83 A drug inhibits nitric oxide formation in the kidney. Which renal hemodynamic pattern is expected? A) Lower resistance; increased GFR B) Higher resistance; decreased GFR C) Lower resistance; decreased sodium excretion D) Higher resistance; increased GFR | back 83 B. Higher resistance; decreased GFR |
front 84 Inhibition of nitric oxide formation eventually causes high blood pressure through which renal effects? A) Increased GFR and natriuresis B) Decreased resistance and natriuresis C) Increased resistance and reduced natriuresis D) Decreased filtration fraction and pressure | back 84 C. Increased resistance and reduced natriuresis |
front 85 Administration of a nitric oxide synthesis inhibitor decreases urinary sodium excretion because it causes which primary renal vascular change? A) Increased renal vascular resistance B) Decreased renal vascular resistance C) Selective venous dilation D) Vasa recta rupture | back 85 A. Increased renal vascular resistance |
front 86 Renal prostaglandins help protect GFR and renal blood flow primarily by opposing vasoconstriction of which vessels? A) Afferent arterioles B) Renal veins C) Collecting ducts D) Ureters | back 86 A. Afferent arterioles |
front 87 A patient taking a prostaglandin-inhibiting drug is at risk for reduced renal perfusion during vasoconstrictor states. Which lost protective action explains this? A) Opposing afferent vasoconstriction B) Increasing efferent vasoconstriction C) Blocking macula densa signaling D) Increasing Bowman capsule pressure | back 87 A. Opposing afferent vasoconstriction |
front 88 Feedback mechanisms intrinsic to the kidneys maintain relatively constant renal blood flow and GFR despite arterial pressure changes. What is this process called A) Autoregulation B) Micturition C) Osmosis D) Protein washdown | back 88 A. Autoregulation |
front 89 Renal autoregulation refers to the kidney’s ability to keep which variables relatively constant despite arterial pressure changes? A) Sodium intake and thirst B) RBF and GFR C) Hematocrit and albumin D) ADH and aldosterone | back 89 B. RBF and GFR |
front 90 The major purpose of renal autoregulation is to maintain a relatively constant GFR and allow precise control of what? A) Water and solute excretion B) Red cell sedimentation C) Bladder wall tension D) Plasma protein synthesis | back 90 A. Water and solute excretion |
front 91 Why does arterial pressure usually affect urine volume less than expected? A) GFR cannot be filtered B) Autoregulation and tubular adaptation C) Plasma proteins freely enter filtrate D) Bowman's pressure always decreases | back 91 B. Autoregulation and tubular adaptation |
front 92 Glomerulotubular balance describes which tubular response when GFR rises? A) Tubular reabsorption increases B) Tubular reabsorption decreases C) Renin release stops completely D) Afferent resistance always rises | back 92 A. Tubular reabsorption increases |
front 93 A patient’s GFR rises, but urine volume increases less than predicted. Which tubular phenomenon helps explain this? A) Proteinuria B) Glomerulotubular balance C) Vesicoureteral reflux D) Minimal change nephropathy | back 93 B. Glomerulotubular balance |
front 94 Tubuloglomerular feedback controls GFR through which two arteriolar mechanisms? A) Afferent and efferent feedback B) Venous and lymphatic feedback C) Cortical and medullary feedback D) Sympathetic and somatic feedback | back 94 A. Afferent and efferent feedback |
front 95 Which feedback system has afferent and efferent arteriolar components that act together to regulate GFR? A) Ureterorenal reflex B) Micturition reflex C) Tubuloglomerular feedback D) Baroreceptor reflex | back 95 C. Tubuloglomerular feedback |
front 96 The juxtaglomerular complex consists of which key cell groups? A) Podocytes and mesangial cells B) Macula densa and JG cells C) Principal and intercalated cells D) Fibroblasts and epithelial cells | back 96 B. Macula densa and JG cells |
front 97 Macula densa cells are located in which nephron region? A) Initial distal tubule B) Proximal straight tubule C) Collecting duct tip D) Thin descending limb | back 97 A. Initial distal tubule |
front 98 Juxtaglomerular cells are located in the walls of which vessels? A) Renal veins only B) Afferent and efferent arterioles C) Peritubular capillaries only D) Interlobar and arcuate arteries | back 98 B. Afferent and efferent arterioles |
front 99 A fall in sodium chloride concentration at the macula densa initiates which afferent arteriolar response? A) Increased afferent resistance B) Decreased afferent resistance C) Complete afferent occlusion D) No change in resistance | back 99 B. Decreased afferent resistance |
front 100 When macula densa NaCl delivery decreases, lowering afferent arteriolar resistance helps restore GFR by increasing which pressure? A) Bowman hydrostatic pressure B) Glomerular hydrostatic pressure C) Renal venous pressure D) Interstitial oncotic pressure | back 100 B. Glomerular hydrostatic pressure |
front 101 Macula densa detection of decreased sodium chloride increases release of which substance from juxtaglomerular cells? A) Calcitriol B) Albumin C) Renin D) Endothelin | back 101 C. Renin |
front 102 A low NaCl signal at the macula densa produces which paired response? A) Afferent resistance falls; renin rises B) Afferent resistance rises; renin falls C) Efferent resistance falls; renin falls D) Bowman pressure rises; renin rises | back 102 A. Afferent resistance falls; renin rises |
front 103 Which statement best distinguishes renal autoregulation from glomerulotubular balance? A) Autoregulation stabilizes GFR; GT balance adjusts reabsorption B) Autoregulation empties bladder; GT balance controls sphincter C) Autoregulation raises proteins; GT balance lowers GFR D) Autoregulation secretes EPO; GT balance activates vitamin D | back 103 A. Autoregulation stabilizes GFR; GT balance adjusts reabsorption |
front 104 A patient has low renal arterial pressure. Macula densa signaling increases renin release, ultimately helping preserve GFR. Which sequence best explains this response? A) Renin; angiotensin I; angiotensin II B) Renin; aldosterone; prostaglandin E C) Endothelin; renin; nitric oxide D) ADH; angiotensinogen; calcitriol | back 104 A. Renin; angiotensin I; angiotensin II |
front 105 Renin released from juxtaglomerular cells functions primarily as which type of molecule? A) Steroid hormone B) Plasma protein buffer C) Enzyme D) Membrane channel | back 105 C. Enzyme |
front 106 Angiotensin II helps return GFR toward normal during reduced renal perfusion by primarily constricting which vessel? A) Afferent arteriole B) Efferent arteriole C) Cortical collecting duct D) Renal vein | back 106 B. Efferent arteriole |
front 107 A patient with decreased renal perfusion relies on angiotensin II to maintain filtration. Which paired effect best describes angiotensin II at the glomerulus? A) Efferent dilation; lower PG B) Afferent dilation; higher PB C) Efferent constriction; higher PG D) Afferent constriction; higher πB | back 107 C. Efferent constriction; higher PG |
front 108 A patient with bilateral renal artery stenosis is started on an ACE inhibitor and develops acute kidney injury. What mechanism best explains the fall in GFR? A) Loss of efferent constriction B) Increased afferent constriction C) Increased Bowman pressure D) Excess podocyte contraction | back 108 A. Loss of efferent constriction |
front 109 Why can ACE inhibitors cause larger-than-usual GFR reductions when renal arterial pressure is low? A) They block angiotensin II formation B) They increase plasma protein filtration C) They increase Bowman capsule pressure D) They activate renal sympathetic nerves | back 109 A. They block angiotensin II formation |
front 110 Which drug class can reduce GFR in renal artery stenosis by blocking angiotensin II action? A) Loop diuretics B) Beta blockers C) Angiotensin receptor antagonists D) Calcium channel blockers | back 110 C. Angiotensin receptor antagonists |
front 111 Renal artery stenosis creates hypertension that may depend on angiotensin II–mediated efferent tone. Which treatment complication is especially important? A) Severe decrease in GFR B) Increased glomerular bleeding C) Increased nephron regeneration D) Severe protein synthesis | back 111 A. Severe decrease in GFR |
front 112 A patient with renal artery stenosis develops acute renal failure after RAAS blockade. Which physiologic support was removed? A) Afferent vasodilation by endothelin B) Efferent constriction by angiotensin II C) Bowman pressure by prostaglandins D) Tubular secretion by aldosterone | back 112 B. Efferent constriction by angiotensin II |
front 113 A renal arteriole responds to increased arterial pressure by resisting stretch and contracting. What autoregulatory mechanism is this? A) Glomerulotubular balance B) Myogenic mechanism C) Ureterorenal reflex D) Donnan effect | back 113 B. Myogenic mechanism |
front 114 The myogenic mechanism helps maintain relatively constant renal blood flow and GFR through which vascular property? A) Resistance to stretching B) Increased protein filtration C) Reduced calcium entry D) Increased tubular secretion | back 114 A. Resistance to stretching |
front 115 Stretch of renal vascular smooth muscle allows increased entry of which ion, causing contraction? A) Sodium B) Potassium C) Calcium D) Chloride | back 115 C. Calcium |
front 116 Which sequence best describes the renal myogenic response to increased pressure? A) Stretch; calcium entry; contraction B) Stretch; sodium exit; relaxation C) Stretch; renin release; dilation D) Stretch; protein loss; filtration | back 116 A. Stretch; calcium entry; contraction |
front 117 A patient begins a high-protein diet. What is the expected effect on renal blood flow and GFR? A) Both decrease B) Both increase C) RBF decreases; GFR increases D) RBF increases; GFR decreases | back 117 B. Both increase |
front 118 A patient develops proximal tubular injury after mercury poisoning. Which tubular transport defect is expected? A) Increased NaCl reabsorption B) Decreased NaCl reabsorption C) Increased albumin filtration D) Decreased calcium filtration | back 118 B. Decreased NaCl reabsorption |
front 119 Large doses of tetracycline damage proximal tubules. Which renal handling change best matches this injury? A) Decreased sodium chloride reabsorption B) Increased protein-bound calcium filtration C) Increased efferent arteriolar resistance D) Decreased Bowman capsule pressure | back 119 A. Decreased sodium chloride reabsorption |
front 120 Which toxic exposures are specifically associated with proximal tubular damage that decreases NaCl reabsorption? A) Mercury and tetracyclines B) Lead and ethanol C) Arsenic and lithium D) Cadmium and acetaminophen | back 120 A. Mercury and tetracyclines |
front 121 The first step in urine production forms a filtrate that is protein-free and lacks red blood cells. What is this fluid called? A) Peritubular fluid B) Glomerular filtrate C) Renal lymph D) Plasma ultraconcentrate | back 121 B. Glomerular filtrate |
front 122 Which composition best describes normal glomerular filtrate? A) Protein-rich with erythrocytes B) Protein-free with salts C) Fat-rich with leukocytes D) Albumin-rich with platelets | back 122 B. Protein-free with salts |
front 123 Which plasma substances are exceptions to free filtration because large portions are protein-bound? A) Calcium and fatty acids B) Sodium and chloride C) Urea and creatinine D) Glucose and bicarbonate | back 123 A. Calcium and fatty acids |
front 124 Minimal change nephropathy causes proteinuria primarily through loss of which barrier property? A) Negative basement membrane charge B) Glomerular hydrostatic pressure C) Bowman capsule pressure D) Peritubular capillary flow | back 124 A. Negative basement membrane charge |
front 125 Minimal change nephropathy is believed to involve abnormal secretion of what factor type? A) T-cell cytokines B) B-cell antibodies C) Platelet thromboxanes D) Macrophage prostaglandins | back 125 A. T-cell cytokines |
front 126 Abnormal T-cell cytokines in minimal change nephropathy are thought to reduce which glomerular barrier feature? A) Anionic charge B) Hydrostatic pressure C) Bowman capsule volume D) Calcium permeability | back 126 A. Anionic charge |
front 127 Why does plasma protein concentration rise across glomerular capillaries? A) Fluid filters into Bowman capsule B) Albumin enters Bowman capsule C) Proteins are secreted by podocytes D) Sodium leaves through erythrocytes | back 127 A. Fluid filters into Bowman capsule |
front 128 Which two factors determine glomerular capillary colloid osmotic pressure? A) Arterial oncotic pressure; filtration fraction B) Bowman pressure; urine flow C) ADH level; sodium intake D) Hematocrit; bladder pressure | back 128 A. Arterial oncotic pressure; filtration fraction |
front 129 Moderate efferent arteriolar constriction raises glomerular hydrostatic pressure. Under what condition can this increase GFR? A) Bowman pressure rises markedly B) Renal blood flow is preserved C) Albumin becomes freely filtered D) Afferent resistance also rises | back 129 B. Renal blood flow is preserved |
front 130 Which statement best describes renal medullary perfusion? A) Medulla receives most renal flow B) Vasa recta supply medullary flow C) Glomeruli directly supply medulla D) Medulla lacks capillary flow | back 130 B. Vasa recta supply medullary flow |
front 131 Which disease-state group is associated with increased endothelin release? A) Pregnancy toxemia; renal failure; uremia B) Diabetes insipidus; tabes dorsalis; reflux C) Nephrotic syndrome; cirrhosis; ascites D) Hypernatremia; burns; diarrhea | back 131 A. Pregnancy toxemia; renal failure; uremia |
front 132 Which renal vessels are relatively protected from angiotensin II–mediated vasoconstriction? A) Preglomerular vessels B) Efferent arterioles C) Cortical veins D) Peritubular capillaries | back 132 A. Preglomerular vessels |
front 133 The afferent arteriole is protected from angiotensin II vasoconstriction partly by increased local release of which vasodilators? A) Aldosterone and ADH B) Prostaglandins and nitric oxide C) Endothelin and norepinephrine D) Renin and angiotensin I | back 133 B. Prostaglandins and nitric oxide |
front 134 Which arteriole is especially protected by vasodilators such as prostaglandins and nitric oxide? A) Afferent arteriole B) Efferent arteriole C) Renal vein D) Ureteral arteriole | back 134 A. Afferent arteriole |
front 135 A patient has elevated angiotensin II. Which paired renal effect is expected from preferential efferent constriction? A) Lower GFR; lower reabsorption B) Higher RBF; lower reabsorption C) Lower RBF; higher reabsorption D) Higher RBF; higher GFR | back 135 C. Lower RBF; higher reabsorption |
front 136 How does angiotensin II increase sodium and water reabsorption? A) It increases peritubular capillary flow B) It decreases peritubular capillary flow C) It blocks proximal sodium transport D) It raises Bowman capsule pressure | back 136 B. It decreases peritubular capillary flow |
front 137 Which set contains renal vasodilators that tend to increase GFR? A) NO, prostaglandins, bradykinin B) Endothelin, epinephrine, norepinephrine C) Angiotensin II, aldosterone, ADH D) Renin, albumin, creatinine | back 137 A. NO, prostaglandins, bradykinin |
front 138 Tubuloglomerular feedback depends on which two major mechanisms? A) Afferent and efferent feedback B) Cortical and medullary reflux C) Sympathetic and somatic feedback D) Glomerular and ureteral reflexes | back 138 A. Afferent and efferent feedback |
front 139 Macula densa cells have Golgi apparatus directed toward arterioles, suggesting which function? A) Secretion toward arterioles B) Filtration of plasma proteins C) Storage of erythropoietin D) Reabsorption of fatty acids | back 139 A. Secretion toward arterioles |
front 140 ACE inhibitors and angiotensin II receptor antagonists can reduce GFR primarily by blocking which support mechanism? A) Efferent arteriolar constriction B) Afferent arteriolar dilation C) Bowman capsule relaxation D) Medullary osmotic washout | back 140 A. Efferent arteriolar constriction |
front 141 What is the expected GFR effect of ACE inhibitors or angiotensin II receptor blockers, especially when renal perfusion pressure is low? A) GFR decreases B) GFR increases C) GFR becomes unchanged D) GFR exceeds RPF | back 141 A. GFR decreases |
front 142 The myogenic mechanism of renal autoregulation depends on vascular smooth muscle doing what during increased blood pressure? A) Resisting stretch by contraction B) Releasing albumin into filtrate C) Increasing sodium secretion D) Relaxing after calcium entry | back 142 A. Resisting stretch by contraction |
front 143 What is the main protective role of the renal myogenic mechanism during increased blood pressure? A) Prevents excessive RBF and GFR rise B) Prevents all sodium filtration C) Increases bladder emptying D) Blocks angiotensin II formation | back 143 A. Prevents excessive RBF and GFR rise |
front 144 A high-protein meal increases amino acid delivery and renal tubular amino acid reabsorption. What happens to renal blood flow and GFR? A) Both decrease B) Both increase C) RBF increases; GFR decreases D) RBF decreases; GFR increases | back 144 B. Both increase |
front 145 What is the long-term renal adaptation to high protein intake? A) Kidney growth with higher RBF/GFR B) Kidney shrinkage with lower RBF/GFR C) Loss of afferent arteriolar response D) Complete macula densa suppression | back 145 A. Kidney growth with higher RBF/GFR |
front 146 Amino acids are reabsorbed primarily in which nephron segment? A) Proximal tubule B) Distal tubule C) Thin ascending limb D) Collecting duct | back 146 A. Proximal tubule |
front 147 Amino acid reabsorption in the proximal tubule increases sodium reabsorption. How does this affect macula densa NaCl delivery? A) It decreases NaCl delivery B) It increases NaCl delivery C) It has no effect D) It blocks renin release | back 147 A. It decreases NaCl delivery |
front 148 Which sequence best explains why high protein intake increases GFR? A) Amino acid reabsorption; lower macula densa NaCl; afferent dilation B) Protein filtration; higher Bowman pressure; afferent dilation C) Amino acid secretion; higher NaCl; efferent dilation D) Albumin reabsorption; lower renin; GFR increase | back 148 A. Amino acid reabsorption; lower macula densa NaCl; afferent dilation |
front 149 Increased blood glucose can increase renal blood flow and GFR through a mechanism similar to amino acids because glucose is reabsorbed where? A) Proximal tubule B) Distal tubule C) Collecting duct D) Loop thin limb | back 149 A. Proximal tubule |
front 150 How does increased glucose reabsorption in the proximal tubule affect macula densa NaCl delivery? A) Decreases NaCl delivery B) Increases NaCl delivery C) Does not affect delivery D) Completely blocks filtration | back 150 A. Decreases NaCl delivery |
front 151 A patient with hyperglycemia has increased proximal sodium-glucose reabsorption. Which tubuloglomerular response can follow? A) Afferent resistance decreases; GFR rises B) Afferent resistance increases; GFR falls C) Efferent resistance decreases; GFR falls D) Bowman pressure increases; GFR falls | back 151 A. Afferent resistance decreases; GFR rises |
front 152 Increased blood glucose is expected to have which renal hemodynamic effect? A) Decreases RBF and GFR B) Increases RBF and GFR C) Increases RBF only D) Decreases GFR only | back 152 B. Increases RBF and GFR |