Exam 33: Elements of Renal Function

A 56-year-old man was admitted to the hospital with a myocardial infarction.At admission,his serum creatinine level was 1.2 mg/dL,and his creatinine clearance rate was 100 mL/minute.Over the next 3 days,he had several periods of hypotension,and his serum creatinine level increased to 3.6 mg/dL.Assuming that he is in steady-state balance for creatinine level (i.e.,amount excreted = amounted produced),what is his predicted creatinine clearance rate?

Which of the following structures is a barrier to the filtration of proteins across the glomerulus?

A substance (Y)is found in the plasma at a concentration of 2 mg/dL.A 24-hour urine collection is performed to determine the renal clearance of Y.The following data are obtained: Urine volume: 1.44 L Urine [Y]: 500 mg/L What is the renal clearance rate of Y?

Starling forces are measured across a capillary wall,and the following values are obtained: Capillary hydrostatic pressure: 30 mm Hg Capillary oncotic pressure: 25 mm Hg Interstitial hydrostatic pressure: 0 mm Hg Interstitial oncotic pressure: 15 mm Hg If the reflection coefficient for protein across this capillary wall is 0.5,what is the pressure and direction of fluid flow across the capillary wall?

The macula densa is part of which of the following structures in the kidney?

The efferent arteriole of some juxtamedullary nephrons enters the renal medulla and becomes which of the following vessels?

According to the tubuloglomerular feedback theory,an increase in tubular fluid NaCl delivery to the macula densa results in which of the following?

A healthy 25-year-old woman donates a kidney to her identical twin,who has chronic renal failure.Her serum creatinine concentration before removal of the kidney is 1.0 mg/dL.After removal of her kidney,her serum creatinine concentration increases to 2.0 mg/dL.One month later her serum creatinine concentration has decreased to 1.5 mg/dL.Which of the following accounts for the fact that her serum creatinine concentration fell from 2.0 to 1.5 mg/dL?

GFR decreases in which of the following conditions?

Which of the following responses to a fall in arterial pressure accounts for the ability of the kidneys to autoregulate glomerular filtration rate (GFR)?