NSG 3850: PATHOPHYSIOLOGY FOR NURSES II EXAM 3 REAL
QUESTIONS WITH CORRECT ANSWERS VERIFIED 2026/2027 PASS
GUARANTEE
Question 1
The functional unit of the kidney responsible for urine formation is
the:
A) Renal pyramid
✓ B) Nephron
C) Renal cortex
D) Collecting duct
Rationale: The nephron is the basic structural and functional unit of the
kidney, responsible for filtration, reabsorption, secretion, and excretion.
Question 2
Which part of the nephron is the primary site of active tubular
reabsorption?
A) Loop of Henle
B) Distal convoluted tubule
✓ C) Proximal convoluted tubule
D) Collecting duct
Rationale: The proximal convoluted tubule (PCT) reabsorbs
approximately 65-70% of filtered sodium, water, glucose, and amino
acids via active transport.
Question 3
,The glomerular filtration rate (GFR) in a healthy adult is
approximately:
A) 25 mL/min
B) 60 mL/min
✓ C) 125 mL/min
D) 200 mL/min
Rationale: Normal GFR is approximately 125 mL/min (180 L/day), of
which roughly 1-2 L is excreted as urine.
Question 4
Which hormone primarily regulates water reabsorption in the
collecting duct?
A) Aldosterone
✓ B) Antidiuretic hormone (ADH)
C) Atrial natriuretic peptide (ANP)
D) Renin
Rationale: ADH (vasopressin) binds to V2 receptors in the collecting
duct, increasing aquaporin-2 channels to enhance water reabsorption.
Question 5
Aldosterone acts on which nephron segment to increase sodium
reabsorption?
A) Proximal tubule
B) Loop of Henle (thick ascending limb)
✓ C) Distal tubule and collecting duct
D) Bowman's capsule
Rationale: Aldosterone binds to mineralocorticoid receptors in the distal
tubule and collecting duct, upregulating Na+/K+-ATPase pumps.
,Question 6
The juxtaglomerular apparatus is primarily responsible for:
A) Urine concentration
✓ B) Renin secretion and tubuloglomerular feedback
C) Erythropoietin production
D) Bicarbonate reabsorption
Rationale: The JGA secretes renin in response to decreased renal
perfusion pressure and low sodium, and participates in tubuloglomerular
feedback.
Question 7
Which of the following best describes the countercurrent multiplier
mechanism?
A) It occurs in the proximal tubule
✓ B) It uses the loop of Henle to establish an osmotic gradient in
the medulla
C) It requires ADH to function
D) It primarily regulates acid-base balance
Rationale: The countercurrent multiplier in the loop of Henle creates a
hyperosmotic medullary interstitium, enabling urine concentration.
Question 8
Erythropoietin is primarily produced by which kidney cells?
A) Mesangial cells
B) Macula densa cells
✓ C) Peritubular interstitial fibroblasts in the cortex
D) Juxtaglomerular cells
, Rationale: Peritubular fibroblasts in the renal cortex produce
erythropoietin in response to hypoxia, stimulating RBC production in
bone marrow.
Question 9
The normal serum creatinine level in adults is approximately:
A) 0.1–0.5 mg/dL
✓ B) 0.6–1.2 mg/dL
C) 2.0–3.0 mg/dL
D) 4.0–5.0 mg/dL
Rationale: Normal serum creatinine ranges from 0.6–1.2 mg/dL.
Elevated levels suggest impaired renal filtration.
Question 10
Which substance is freely filtered but NOT reabsorbed by the
kidney, making it ideal for GFR measurement?
A) Creatinine
B) Urea
✓ C) Inulin
D) PAH (para-aminohippurate)
Rationale: Inulin is the gold standard for GFR measurement as it is
freely filtered and neither secreted nor reabsorbed.
Question 11
The thick ascending limb of Henle's loop is impermeable to:
A) Sodium
B) Chloride
✓ C) Water
D) Potassium
QUESTIONS WITH CORRECT ANSWERS VERIFIED 2026/2027 PASS
GUARANTEE
Question 1
The functional unit of the kidney responsible for urine formation is
the:
A) Renal pyramid
✓ B) Nephron
C) Renal cortex
D) Collecting duct
Rationale: The nephron is the basic structural and functional unit of the
kidney, responsible for filtration, reabsorption, secretion, and excretion.
Question 2
Which part of the nephron is the primary site of active tubular
reabsorption?
A) Loop of Henle
B) Distal convoluted tubule
✓ C) Proximal convoluted tubule
D) Collecting duct
Rationale: The proximal convoluted tubule (PCT) reabsorbs
approximately 65-70% of filtered sodium, water, glucose, and amino
acids via active transport.
Question 3
,The glomerular filtration rate (GFR) in a healthy adult is
approximately:
A) 25 mL/min
B) 60 mL/min
✓ C) 125 mL/min
D) 200 mL/min
Rationale: Normal GFR is approximately 125 mL/min (180 L/day), of
which roughly 1-2 L is excreted as urine.
Question 4
Which hormone primarily regulates water reabsorption in the
collecting duct?
A) Aldosterone
✓ B) Antidiuretic hormone (ADH)
C) Atrial natriuretic peptide (ANP)
D) Renin
Rationale: ADH (vasopressin) binds to V2 receptors in the collecting
duct, increasing aquaporin-2 channels to enhance water reabsorption.
Question 5
Aldosterone acts on which nephron segment to increase sodium
reabsorption?
A) Proximal tubule
B) Loop of Henle (thick ascending limb)
✓ C) Distal tubule and collecting duct
D) Bowman's capsule
Rationale: Aldosterone binds to mineralocorticoid receptors in the distal
tubule and collecting duct, upregulating Na+/K+-ATPase pumps.
,Question 6
The juxtaglomerular apparatus is primarily responsible for:
A) Urine concentration
✓ B) Renin secretion and tubuloglomerular feedback
C) Erythropoietin production
D) Bicarbonate reabsorption
Rationale: The JGA secretes renin in response to decreased renal
perfusion pressure and low sodium, and participates in tubuloglomerular
feedback.
Question 7
Which of the following best describes the countercurrent multiplier
mechanism?
A) It occurs in the proximal tubule
✓ B) It uses the loop of Henle to establish an osmotic gradient in
the medulla
C) It requires ADH to function
D) It primarily regulates acid-base balance
Rationale: The countercurrent multiplier in the loop of Henle creates a
hyperosmotic medullary interstitium, enabling urine concentration.
Question 8
Erythropoietin is primarily produced by which kidney cells?
A) Mesangial cells
B) Macula densa cells
✓ C) Peritubular interstitial fibroblasts in the cortex
D) Juxtaglomerular cells
, Rationale: Peritubular fibroblasts in the renal cortex produce
erythropoietin in response to hypoxia, stimulating RBC production in
bone marrow.
Question 9
The normal serum creatinine level in adults is approximately:
A) 0.1–0.5 mg/dL
✓ B) 0.6–1.2 mg/dL
C) 2.0–3.0 mg/dL
D) 4.0–5.0 mg/dL
Rationale: Normal serum creatinine ranges from 0.6–1.2 mg/dL.
Elevated levels suggest impaired renal filtration.
Question 10
Which substance is freely filtered but NOT reabsorbed by the
kidney, making it ideal for GFR measurement?
A) Creatinine
B) Urea
✓ C) Inulin
D) PAH (para-aminohippurate)
Rationale: Inulin is the gold standard for GFR measurement as it is
freely filtered and neither secreted nor reabsorbed.
Question 11
The thick ascending limb of Henle's loop is impermeable to:
A) Sodium
B) Chloride
✓ C) Water
D) Potassium
