Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A -
Chamberlain
1. Which part of the nephron is primarily responsible for
reabsorbing the majority of water and solutes?
A. Proximal tubule
B. Loop of Henle
C. Distal tubule
D. Collecting duct
Correct answer: A
Rationale: The proximal tubule reabsorbs ~65% of filtered water,
sodium, and nearly all glucose.
2. Which hormone increases water reabsorption in the collecting
duct?
A. Aldosterone
B. ADH
,C. ANP
D. Renin
Correct answer: B
Rationale: ADH promotes aquaporin insertion, allowing water to be
reabsorbed and urine to concentrate.
3. Which nephron segment actively reabsorbs ions but is
impermeable to water?
A. Descending Loop of Henle
B. Ascending Loop of Henle
C. Proximal tubule
D. Collecting duct
Correct answer: B
Rationale: The thick ascending limb actively transports Na+, K+,
and Cl− while preventing water movement.
4. Which hormone increases sodium reabsorption and potassium
excretion in distal nephron?
A. ADH
B. Aldosterone
C. ANP
D. Angiotensin II
,Correct answer: B
Rationale: Aldosterone acts on distal tubules and collecting ducts to
regulate electrolyte balance.
5. Which hormone is secreted by atrial cells to reduce blood
volume?
A. ADH
B. ANP
C. Aldosterone
D. Renin
Correct answer: B
Rationale: ANP promotes natriuresis and diuresis to lower blood
volume and pressure.
6. Which stimulus triggers renin secretion?
A. High sodium
B. Low blood pressure
C. Low potassium
D. ANP
Correct answer: B
Rationale: Low BP triggers juxtaglomerular cells to release renin to
activate RAAS.
7. Which nephron segment establishes the medullary osmotic
gradient?
, A. Proximal tubule
B. Loop of Henle
C. Distal tubule
D. Collecting duct
Correct answer: B
Rationale: Countercurrent multiplication in the Loop of Henle
concentrates the medulla.
8. Which hormone responds to increased plasma osmolarity?
A. ADH
B. Aldosterone
C. ANP
D. Renin
Correct answer: A
Rationale: ADH conserves water by increasing collecting duct
permeability.
9. Which hormone stimulates potassium secretion in exchange for
sodium?
A. ADH
B. Aldosterone
C. ANP
D. Angiotensin II