Anatomy of nephrons MCQs With Answer

Anatomy of nephrons MCQs With Answer is a concise, keyword-rich introduction for B. Pharm students focusing on nephron anatomy, structure, and renal microanatomy. This resource covers glomerulus, Bowman’s capsule, proximal tubule, loop of Henle, distal convoluted tubule, collecting duct, juxtaglomerular apparatus, podocytes, mesangial cells, vasa recta, and filtration barriers with clear emphasis on functional relevance for drug action and renal physiology. Ideal for exam preparation and concept reinforcement, these MCQs with answers help strengthen understanding of filtration, reabsorption, secretion, countercurrent mechanisms, and transporter physiology. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. Which structure forms the blood–urine filtration barrier in the renal corpuscle?

• Endothelial fenestrations, glomerular basement membrane, and podocyte slit diaphragms
• Basement membrane and proximal tubular brush border
• Peritubular capillary endothelium and collecting duct epithelium
• Loop of Henle thin segment and macula densa

Correct Answer: Endothelial fenestrations, glomerular basement membrane, and podocyte slit diaphragms

Q2. Which cell type in the glomerulus is primarily responsible for structural support and modulation of filtration surface area?

• Podocytes
• Mesangial cells
• Juxtaglomerular cells
• Endothelial cells

Correct Answer: Mesangial cells

Q3. Which part of the nephron has prominent brush border and is the main site for bulk reabsorption of glucose, amino acids, and bicarbonate?

• Proximal convoluted tubule
• Distal convoluted tubule
• Thin descending limb of Henle
• Collecting duct

Correct Answer: Proximal convoluted tubule

Q4. The thin descending limb of Henle is primarily permeable to which of the following?

• Water
• Sodium and chloride
• Urea actively transported
• Glucose

Correct Answer: Water

Q5. Which transporter is most important in the early proximal tubule for sodium-coupled glucose reabsorption?

• SGLT2 (sodium-glucose cotransporter 2)
• NKCC2 (Na-K-2Cl cotransporter)
• ENaC (epithelial sodium channel)
• ROMK (renal outer medullary potassium channel)

Correct Answer: SGLT2 (sodium-glucose cotransporter 2)

Q6. Juxtamedullary nephrons are specialized to:

• Establish a corticomedullary osmotic gradient for urine concentration
• Filter plasma at very low pressures only
• Produce renin exclusively
• Secrete large amounts of bicarbonate

Correct Answer: Establish a corticomedullary osmotic gradient for urine concentration

Q7. The macula densa senses which parameter to regulate glomerular filtration rate via tubuloglomerular feedback?

• Chloride concentration or NaCl delivery in the distal tubule
• Blood pH in the proximal tubule
• Urine flow in the collecting duct
• Plasma glucose concentration

Correct Answer: Chloride concentration or NaCl delivery in the distal tubule

Q8. Podocyte slit diaphragm proteins such as nephrin are essential for preventing:

• Proteinuria by maintaining filtration slit integrity
• Hydrochloric acid secretion
• Active glucose uptake in the loop of Henle
• Renin secretion from juxtaglomerular cells

Correct Answer: Proteinuria by maintaining filtration slit integrity

Q9. The primary driving force for filtration across glomerular capillaries is:

• Glomerular capillary hydrostatic pressure
• Bowman’s space hydrostatic pressure
• Plasma colloid osmotic pressure
• Active transport by podocytes

Correct Answer: Glomerular capillary hydrostatic pressure

Q10. Which segment of the nephron contains the Na-K-2Cl cotransporter targeted by loop diuretics?

• Thick ascending limb of Henle
• Thin descending limb
• Proximal tubule
• Distal convoluted tubule

Correct Answer: Thick ascending limb of Henle

Q11. The vasa recta function mainly as:

• A countercurrent exchanger preserving the medullary osmotic gradient
• Primary site of glomerular filtration
• Major site of hormonal secretion of ADH
• Storage for urine before excretion

Correct Answer: A countercurrent exchanger preserving the medullary osmotic gradient

Q12. Aldosterone acts primarily on which part of the nephron to increase sodium reabsorption?

• Principal cells of the cortical collecting duct
• Proximal convoluted tubule cells
• Podocytes in Bowman’s capsule
• Macula densa cells

Correct Answer: Principal cells of the cortical collecting duct

Q13. Which structure surrounds the glomerulus and collects the filtrate?

• Bowman’s capsule
• Proximal tubule
• Renal pelvis
• Collecting duct

Correct Answer: Bowman’s capsule

Q14. What is the primary role of the proximal tubule mitochondria-rich cells?

• Provide ATP for active transport processes like Na+/K+ ATPase
• Secrete renin into the bloodstream
• Produce erythropoietin
• Store filtrate temporarily

Correct Answer: Provide ATP for active transport processes like Na+/K+ ATPase

Q15. The thick ascending limb is often called the “diluting segment” because it:

• Reabsorbs salts without water, decreasing tubular fluid osmolarity
• Is highly permeable to water but not to ions
• Secretes large amounts of urea into the lumen
• Reabsorbs glucose actively

Correct Answer: Reabsorbs salts without water, decreasing tubular fluid osmolarity

Q16. Which layer of the glomerular basement membrane contains heparan sulfate and contributes to charge-selective filtration?

• Lamina lucida and lamina densa with heparan sulfate proteoglycans
• Podocyte cytoskeleton
• Bowman’s capsule epithelial layer only
• Peritubular interstitium

Correct Answer: Lamina lucida and lamina densa with heparan sulfate proteoglycans

Q17. Which cell type synthesizes and secretes renin in response to decreased renal perfusion?

• Juxtaglomerular (granular) cells
• Podocytes
• Mesangial cells
• Principal cells

Correct Answer: Juxtaglomerular (granular) cells

Q18. Filtration fraction is defined as:

• GFR divided by renal plasma flow
• Renal plasma flow divided by GFR
• Urine output divided by GFR
• Glomerular capillary pressure minus Bowman’s space pressure

Correct Answer: GFR divided by renal plasma flow

Q19. Which component of the slit diaphragm is mutated in congenital nephrotic syndrome leading to massive proteinuria?

• Nephrin
• SGLT2
• NKCC2
• Uromodulin

Correct Answer: Nephrin

Q20. The peritubular capillaries are primarily involved in:

• Reabsorption of solutes and water from the tubular fluid back to the blood
• Production of filtrate from plasma
• Concentration of urine via countercurrent multiplication
• Secretion of erythropoietin directly into filtrate

Correct Answer: Reabsorption of solutes and water from the tubular fluid back to the blood

Q21. Which portion of the nephron is impermeable to water under low ADH conditions, contributing to dilute urine?

• Thick ascending limb of Henle
• Thin descending limb
• Collecting duct with high ADH
• Proximal convoluted tubule

Correct Answer: Thick ascending limb of Henle

Q22. Which nephron segment reabsorbs the largest proportion of filtered bicarbonate?

• Proximal convoluted tubule
• Distal convoluted tubule
• Collecting duct
• Loop of Henle

Correct Answer: Proximal convoluted tubule

Q23. Macula densa-derived signals that cause afferent arteriolar constriction are typically triggered by:

• Increased NaCl delivery to the distal tubule
• Decreased intraglomerular pressure
• Low plasma potassium
• High urinary glucose

Correct Answer: Increased NaCl delivery to the distal tubule

Q24. Which statement best describes cortical nephrons?

• They have short loops of Henle and are mainly involved in solute/water reabsorption near the cortex
• They extend deep into the inner medulla and set up the osmotic gradient
• They are the exclusive site of renin secretion
• They lack proximal tubules

Correct Answer: They have short loops of Henle and are mainly involved in solute/water reabsorption near the cortex

Q25. The main effect of antidiuretic hormone (ADH) on the collecting duct is to:

• Increase water permeability via insertion of aquaporin-2 channels
• Block Na+/K+ ATPase in principal cells
• Stimulate gluconeogenesis in the collecting duct
• Increase filtration at the glomerulus directly

Correct Answer: Increase water permeability via insertion of aquaporin-2 channels

Q26. Which ion is secreted into the urine in exchange for sodium in the principal cells under aldosterone influence?

• Potassium
• Calcium
• Magnesium
• Glucose

Correct Answer: Potassium

Q27. The epithelial cells of the proximal tubule are characterized histologically by:

• Brush border microvilli and abundant mitochondria
• Flat squamous epithelium with few mitochondria
• Stratified columnar epithelium
• Mucus-secreting goblet cells

Correct Answer: Brush border microvilli and abundant mitochondria

Q28. Which mechanism helps the kidney concentrate urine by trapping urea in the inner medulla?

• Urea recycling between collecting ducts and loop of Henle
• Active secretion of urea from glomerulus
• Direct filtration of urea into Bowman’s capsule only
• Complete impermeability of collecting duct to urea

Correct Answer: Urea recycling between collecting ducts and loop of Henle

Q29. The glomerular filtration rate (GFR) is most directly proportional to which of the following?

• Net filtration pressure and filtration coefficient (Kf)
• Plasma protein concentration only
• Urine flow rate exclusively
• Collecting duct water permeability

Correct Answer: Net filtration pressure and filtration coefficient (Kf)

Q30. Which structural feature of podocytes contributes to selective molecular filtration?

• Interdigitating foot processes forming slit diaphragms
• Basal cilia sensing flow
• Secretory granules releasing renin
• Thick brush border

Correct Answer: Interdigitating foot processes forming slit diaphragms

Q31. The main role of intercalated cells in the collecting duct is to:

• Regulate acid–base balance via H+ and HCO3− transport
• Reabsorb most filtered glucose
• Generate the corticomedullary osmotic gradient
• Secrete renin in response to hypotension

Correct Answer: Regulate acid–base balance via H+ and HCO3− transport

Q32. Which segment actively reabsorbs calcium under the influence of parathyroid hormone (PTH)?

• Distal convoluted tubule
• Proximal tubule
• Thin descending limb
• Collecting duct

Correct Answer: Distal convoluted tubule

Q33. The term “filtration slit” refers to:

• The narrow gap between adjacent podocyte foot processes
• The lumen of the proximal tubule
• The opening of the collecting duct into the renal pelvis
• The endothelial pores in peritubular capillaries

Correct Answer: The narrow gap between adjacent podocyte foot processes

Q34. Which transporter is most important for sodium reabsorption in the distal convoluted tubule and targeted by thiazide diuretics?

• NaCl cotransporter (NCC)
• NKCC2
• SGLT2
• Aquaporin-2

Correct Answer: NaCl cotransporter (NCC)

Q35. The filtration coefficient (Kf) is determined by which two factors?

• Surface area for filtration and hydraulic conductivity of the barrier
• Plasma glucose and urea concentrations
• ADH and aldosterone levels only
• Renal nerve activity and macula densa thickness

Correct Answer: Surface area for filtration and hydraulic conductivity of the barrier

Q36. Which segment of the nephron is the primary site for secretion of organic anions and cations?

• Proximal convoluted tubule
• Loop of Henle
• Distal convoluted tubule
• Glomerulus

Correct Answer: Proximal convoluted tubule

Q37. Which statement about the distal convoluted tubule (DCT) is correct?

• It performs fine tuning of electrolytes and is influenced by PTH and thiazides
• It has a prominent brush border like the proximal tubule
• It is highly permeable to water regardless of ADH
• It actively secretes large proteins into urine

Correct Answer: It performs fine tuning of electrolytes and is influenced by PTH and thiazides

Q38. Which anatomical relationship enables tubuloglomerular feedback between the macula densa and glomerulus?

• The proximity of the macula densa in the DCT to the afferent and efferent arterioles
• The communication between collecting duct and ureter
• The direct innervation of proximal tubule by sympathetic fibers
• The connection between vasa recta and Bowman’s capsule

Correct Answer: The proximity of the macula densa in the DCT to the afferent and efferent arterioles

Q39. Which part of the nephron concentrates urine by passive water movement into a hyperosmotic interstitium?

• Thin descending limb of Henle
• Thick ascending limb of Henle
• Distal convoluted tubule
• Glomerulus

Correct Answer: Thin descending limb of Henle

Q40. Basement membranes in the glomerulus are primarily composed of which molecules?

• Type IV collagen, laminin, and heparan sulfate proteoglycans
• Keratin and cellulose
• Elastin and fibrinogen exclusively
• Actin and myosin filaments

Correct Answer: Type IV collagen, laminin, and heparan sulfate proteoglycans

Q41. Which structure is most responsible for preventing backflow of urine from the bladder to the ureter?

• Ureterovesical junction (functional flap-valve mechanism)
• Glomerular basement membrane
• Renal capsule
• Bladder trigone only

Correct Answer: Ureterovesical junction (functional flap-valve mechanism)

Q42. What is the effect of ANP (atrial natriuretic peptide) on the nephron?

• Decreases sodium reabsorption and increases GFR by dilating afferent arteriole
• Stimulates aldosterone release to retain sodium
• Inhibits ADH synthesis in the posterior pituitary
• Increases glucose reabsorption in the proximal tubule

Correct Answer: Decreases sodium reabsorption and increases GFR by dilating afferent arteriole

Q43. Which structural feature distinguishes the cortical collecting duct from the medullary collecting duct histologically?

• Cortical collecting duct has more intercalated and principal cells and is located in cortex; medullary has fewer and different permeability traits
• Cortical collecting duct has cilia for flow sensing
• Medullary collecting duct lacks epithelial lining
• Cortical collecting duct secretes renin

Correct Answer: Cortical collecting duct has more intercalated and principal cells and is located in cortex; medullary has fewer and different permeability traits

Q44. Which of the following describes the countercurrent multiplier mechanism?

• Active salt transport in the thick ascending limb and passive water movement in descending limb create medullary osmotic gradient
• Active water reabsorption in both limbs raises medullary osmolarity
• Urea secretion in the cortex multiplies urine concentration
• Peritubular capillaries actively pump salts into the lumen

Correct Answer: Active salt transport in the thick ascending limb and passive water movement in descending limb create medullary osmotic gradient

Q45. Which anatomical component directly senses renal perfusion pressure to influence renin release?

• Baroreceptors in afferent arteriole juxtaglomerular cells
• Macula densa sensing K+
• Podocyte foot processes
• Peritubular capillary endothelial receptors for urea

Correct Answer: Baroreceptors in afferent arteriole juxtaglomerular cells

Q46. Which transporter in the basolateral membrane of proximal tubule cells maintains sodium gradient for apical reabsorption?

• Na+/K+ ATPase
• H+/K+ ATPase
• Glucose transporter GLUT2 on apical membrane
• Apical aquaporin-1 channel

Correct Answer: Na+/K+ ATPase

Q47. The renal corpuscle includes which two major components?

• Glomerulus and Bowman’s capsule
• Proximal and distal tubules
• Loop of Henle and vasa recta
• Collecting duct and renal pelvis

Correct Answer: Glomerulus and Bowman’s capsule

Q48. Which statement about mesangial cells is correct?

• They provide structural support, phagocytose debris, and regulate capillary flow via contraction
• They synthesize renin in response to low NaCl
• They form the slit diaphragm between podocytes
• They line the lumen of the collecting duct

Correct Answer: They provide structural support, phagocytose debris, and regulate capillary flow via contraction

Q49. In the nephron, where does obligatory water reabsorption occur regardless of ADH levels?

• Proximal convoluted tubule
• Collecting duct
• Distal convoluted tubule
• Thin ascending limb

Correct Answer: Proximal convoluted tubule

Q50. Which feature distinguishes juxtaglomerular cells histologically?

• Granules containing renin and a modified smooth muscle appearance in afferent arteriole
• Extensive microvilli and brush border
• Multiple cilia projecting into the lumen of Bowman’s capsule
• Keratinized epithelial plaques

Correct Answer: Granules containing renin and a modified smooth muscle appearance in afferent arteriole

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

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