GFR practice quiz

Which renal process forms a plasma-like filtrate from blood within the renal corpuscle?

• Tubular secretion in distal nephron

• Tubular reabsorption in proximal tubule

• Glomerular filtration in renal corpuscle

• Water conservation in collecting duct

A solute is moved from peritubular capillaries into the nephron lumen to be excreted. Which renal process best describes this movement?

• Tubular secretion into the filtrate

• Water conservation via aquaporins

• Tubular reabsorption back to the blood

• Glomerular filtration through fenestrated capillaries

Which component of the glomerular filtration barrier primarily repels negatively charged plasma proteins?

• Bowman’s capsule parietal layer

• Fenestrated endothelium of capillaries

• Negatively charged basement membrane

• Podocyte foot processes alone

A neutral solute with a molecular size of about 3 nm is most likely to appear in the initial ultrafiltrate. Which example best fits this profile?

• Large lipoprotein particle

• Hemoglobin within red cells

• Albumin bound calcium complex

• Glucose in free solution

During a disease that effaces podocyte foot processes and widens filtration slits, which clinical change is most expected first?

• Increase in afferent arteriolar tone

• Marked hematuria without protein

• Onset of proteinuria in the urine

• Rise in glucose reabsorption capacity

Which force opposes glomerular filtration within the capillary tuft?

• Bowman’s space oncotic pressure

• Glomerular hydrostatic blood pressure

• Capsular space hydrostatic pressure

• Afferent arteriolar pressure surge

Net Filtration Pressure (NFP) in the glomerulus is best defined as:

• Filtration minus reabsorption pressures

• Difference between afferent and efferent pressures

• Product of Kf and hydrostatic pressure

• Sum of all hydrostatic and osmotic pressures

If π_GC (colloid osmotic pressure in glomerular capillaries) rises along the capillary while P_GC and P_BS remain constant, what happens to NFP along the length of the glomerulus?

• NFP decreases progressively

• NFP increases progressively

• NFP reverses and favors reabsorption

• NFP remains unchanged

Given Kf = 12.5 ml/mmHg/min and NFP = 10 mmHg, what are the GFR per minute and approximate daily filtrate volume?

• 100 ml/min and ~144 L/day

• 135 ml/min and ~200 L/day

• 115 ml/min and ~160 L/day

• 125 ml/min and ~180 L/day

Which statement best describes the myogenic response in the afferent arteriole?

• Macula densa senses NaCl to constrict efferent arteriole

• Endothelium releases NO to increase filtration rapidly

• Sympathetic nerves dilate arterioles to raise GFR

• Smooth muscle contracts when stretched to stabilize flow