Absorption of digested food MCQs With Answer

Absorption of digested food MCQs With Answer is a focused review for B. Pharm students covering intestinal absorption mechanisms, transporters, and factors influencing bioavailability. This concise guide explains enterocyte uptake, paracellular pathways, carrier-mediated transport (SGLT1, GLUT2, PEPT1), lipid absorption via micelles and chylomicrons, and the role of bile salts and pancreatic enzymes. It highlights physiological determinants—surface area, pH, transit time—and pathological or pharmacological modifiers affecting absorption and first-pass metabolism. Designed to deepen understanding of nutrient-to-systemic transfer and drug–food interactions, these practice questions target both conceptual and applied knowledge. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. Which intestinal transporter primarily mediates active uptake of glucose at the apical membrane of enterocytes?

• SGLT1 (sodium–glucose co-transporter 1)
• GLUT2 (facilitative glucose transporter)
• PEPT1 (peptide transporter)
• CFTR (chloride channel)

Correct Answer: SGLT1 (sodium–glucose co-transporter 1)

Q2. Which mechanism is mainly responsible for absorption of most di- and tri-peptides in the small intestine?

• Facilitated diffusion via GLUT transporters
• Active cotransport via PEPT1
• Paracellular diffusion through tight junctions
• Endocytosis by M cells

Correct Answer: Active cotransport via PEPT1

Q3. Micelle formation in the intestinal lumen is essential for absorption of which nutrients?

• Water-soluble vitamins (B and C)
• Short-chain fatty acids
• Fat-soluble vitamins and long-chain fatty acids
• Amino acids

Correct Answer: Fat-soluble vitamins and long-chain fatty acids

Q4. Which structure in the intestinal mucosa increases absorptive surface area most significantly?

• Lacteals
• Crypts of Lieberkühn
• Villi and microvilli (brush border)
• Peyer’s patches

Correct Answer: Villi and microvilli (brush border)

Q5. After absorption, short-chain fatty acids are transported primarily via which route?

• Lymphatic transport as chylomicrons
• Portal blood directly to the liver
• Transport in bile back to the intestine
• Stored in enterocyte lysosomes

Correct Answer: Portal blood directly to the liver

Q6. Which enzyme is critical for hydrolysis of dietary triglycerides before lipid absorption?

• Lactase
• Pancreatic lipase (with colipase)
• Sucrase-isomaltase
• Pepsin

Correct Answer: Pancreatic lipase (with colipase)

Q7. Chylomicrons formed in enterocytes are secreted into which structure?

• Portal vein
• Lacteal (intestinal lymphatic)
• Hepatic artery
• Capillary blood of villi

Correct Answer: Lacteal (intestinal lymphatic)

Q8. Which statement best describes paracellular absorption?

• Carrier-mediated uptake across brush border proteins
• Transport through tight junctions between enterocytes
• Endocytosis of macromolecules into enterocytes
• Facilitated diffusion via ion channels

Correct Answer: Transport through tight junctions between enterocytes

Q9. PEPT1 primarily transports which substrates?

• Glucose and galactose
• Monosaccharides
• Di- and tri-peptides and peptide-like drugs
• Lipid monomers

Correct Answer: Di- and tri-peptides and peptide-like drugs

Q10. The “pH partition hypothesis” influences drug and nutrient absorption by explaining the effect of:

• Lipid solubility independent of ionization
• Degree of ionization and membrane permeability in different pH environments
• Active transport specificity
• Lymphatic uptake of lipophilic drugs

Correct Answer: Degree of ionization and membrane permeability in different pH environments

Q11. Which transporter mediates facilitated diffusion of glucose from enterocyte basolateral membrane into blood?

• SGLT1
• GLUT2
• PEPT1
• ASBT (apical sodium-dependent bile acid transporter)

Correct Answer: GLUT2

Q12. Which factor would decrease intestinal absorption of a weakly acidic drug?

• Lowering gastric pH (more acidic)
• Increasing intestinal pH (more basic)
• Complexation with divalent cations
• Formulation as a lipid-soluble prodrug

Correct Answer: Complexation with divalent cations

Q13. Bile salts facilitate lipid absorption by:

• Increasing pancreatic enzyme secretion only
• Forming micelles that solubilize fatty acids and monoglycerides
• Transporting lipids directly into the portal vein
• Inhibiting lipase activity

Correct Answer: Forming micelles that solubilize fatty acids and monoglycerides

Q14. Which vitamin requires micellar solubilization and chylomicron transport for absorption?

• Vitamin C
• Vitamin B12
• Vitamin A (retinol)
• Folic acid

Correct Answer: Vitamin A (retinol)

Q15. Which condition increases intestinal permeability and may enhance paracellular drug absorption?

• Dehydration
• Celiac disease with villous atrophy
• Constipation with slowed transit
• Hypochlorhydria

Correct Answer: Celiac disease with villous atrophy

Q16. First-pass hepatic metabolism primarily affects drugs absorbed via which route?

• Lymphatic absorption into systemic circulation
• Direct absorption into the portal vein from enterocytes
• Transdermal absorption
• Buccal mucosa absorption

Correct Answer: Direct absorption into the portal vein from enterocytes

Q17. Which transporter is important for bile acid reabsorption in the ileum?

• ASBT (apical sodium-dependent bile acid transporter)
• PEPT1
• SGLT1
• OATP (organic anion transporting polypeptide)

Correct Answer: ASBT (apical sodium-dependent bile acid transporter)

Q18. Which process best describes transcytosis in enterocytes?

• Passive diffusion of small hydrophilic molecules
• Endocytosis, vesicular transport across the cell, then exocytosis
• Paracellular passage through tight junctions
• Carrier-mediated facilitated diffusion

Correct Answer: Endocytosis, vesicular transport across the cell, then exocytosis

Q19. Which factor most directly reduces nutrient absorption by decreasing surface area?

• Increased bile salt concentration
• Resection of a segment of small intestine
• Enhanced pancreatic secretion
• High dietary fiber intake

Correct Answer: Resection of a segment of small intestine

Q20. Which statement about chylomicron formation is correct?

• Chylomicrons are assembled in the Golgi and secreted into portal blood
• Triglycerides are re-esterified in enterocytes before packaging into chylomicrons
• Chylomicrons contain only cholesterol and no triglycerides
• Chylomicrons directly enter hepatic sinusoids

Correct Answer: Triglycerides are re-esterified in enterocytes before packaging into chylomicrons

Q21. Which intestinal region is the principal site for absorption of iron (non-heme) and folate?

• Duodenum for iron; jejunum for folate
• Ileum for iron; colon for folate
• Stomach for both
• Jejunum for iron; ileum for folate

Correct Answer: Duodenum for iron; jejunum for folate

Q22. Active transport across the intestinal epithelium requires which of the following?

• ATP or ion gradients to drive carrier proteins
• High lipid solubility only
• Micelle formation
• Paracellular junction relaxation

Correct Answer: ATP or ion gradients to drive carrier proteins

Q23. Which hub protein on the enterocyte brush border activates pancreatic zymogens needed for protein digestion?

• Enterokinase (enteropeptidase)
• Pepsinogen
• Trypsin inhibitor
• Amylase

Correct Answer: Enterokinase (enteropeptidase)

Q24. Lipid-soluble drugs are more likely to be absorbed via which pathway?

• Carrier-mediated uptake by PEPT1
• Paracellular route through tight junctions
• Transcellular passive diffusion and possible lymphatic transport
• Active sodium-dependent transport

Correct Answer: Transcellular passive diffusion and possible lymphatic transport

Q25. Which is a major determinant of the rate of passive diffusion across the intestinal epithelium?

• Molecular size and lipid solubility (partition coefficient)
• Presence of bile salts only
• Number of Peyer’s patches
• Activity of brush border enzymes

Correct Answer: Molecular size and lipid solubility (partition coefficient)

Q26. Which peptide-based drug uptake leverages the same transporter as dietary dipeptides?

• Insulin administered orally
• ACE inhibitors absorbed via PEPT1
• Oral aminoglycosides via paracellular route
• Fat-soluble vitamins via micelles

Correct Answer: ACE inhibitors absorbed via PEPT1

Q27. Which change would decrease oral bioavailability of a drug absorbed in the small intestine?

• Formulating as a highly lipophilic prodrug targeting lymphatics
• Co-administration with a CYP3A4 inducer increasing first-pass metabolism
• Using a controlled-release formulation prolonging jejunal delivery
• Administration with fatty meal that enhances micelle formation

Correct Answer: Co-administration with a CYP3A4 inducer increasing first-pass metabolism

Q28. Which transporter mediates absorption of bile salts from the terminal ileum back to the enterocyte?

• NTCP (sodium taurocholate co-transporting polypeptide)
• ASBT (apical sodium-dependent bile acid transporter)
• GLUT5 (fructose transporter)
• PEPT2

Correct Answer: ASBT (apical sodium-dependent bile acid transporter)

Q29. Which scenario favors lymphatic transport of a lipophilic drug?

• Drug forms highly water-soluble salts
• Drug associates with chylomicron triglycerides after a high-fat meal
• Drug is small and hydrophilic
• Co-administered with chelators

Correct Answer: Drug associates with chylomicron triglycerides after a high-fat meal

Q30. Which transporter facilitates fructose absorption across the apical membrane of enterocytes?

• GLUT5
• SGLT1
• GLUT2 at apical membrane only
• PEPT1

Correct Answer: GLUT5

Q31. How does intestinal transit time affect nutrient and drug absorption?

• Faster transit always increases absorption
• Very rapid transit can reduce contact time and decrease absorption
• Transit time has no impact on absorption
• Slower transit always decreases absorption

Correct Answer: Very rapid transit can reduce contact time and decrease absorption

Q32. Which factor enhances absorption of weak bases in the stomach?

• Low gastric pH causing them to be ionized
• High gastric pH causing them to be non-ionized
• Formation of micelles
• Co-administration with bile salts

Correct Answer: Low gastric pH causing them to be ionized

Q33. Which of the following best explains why large hydrophilic peptides are poorly absorbed orally?

• They form micelles preventing uptake
• They are extensively degraded by proteases and have low membrane permeability
• They are rapidly transported via lymphatics
• They easily cross tight junctions paracellularly

Correct Answer: They are extensively degraded by proteases and have low membrane permeability

Q34. What role do tight junctions play in intestinal absorption?

• They exclusively permit transcellular diffusion
• They regulate paracellular permeability between enterocytes
• They catalyze enzymatic digestion
• They package nutrients into chylomicrons

Correct Answer: They regulate paracellular permeability between enterocytes

Q35. Which pathology reduces bile salt availability and thus impairs fat-soluble vitamin absorption?

• Pancreatic exocrine hyperactivity
• Cholestasis or obstructive jaundice
• Hyperthyroidism
• Increased ileal bile acid reabsorption

Correct Answer: Cholestasis or obstructive jaundice

Q36. Which experimental model is commonly used to study intestinal drug absorption in vitro?

• HepG2 hepatocyte cultures
• Caco-2 cell monolayers
• Cardiac myocyte preparations
• Red blood cell suspensions

Correct Answer: Caco-2 cell monolayers

Q37. Which molecule primarily facilitates basolateral efflux of bile acids from ileal enterocytes into portal blood?

• OSTα/OSTβ (organic solute transporter alpha-beta)
• P-glycoprotein (P-gp)
• PEPT1
• SGLT1

Correct Answer: OSTα/OSTβ (organic solute transporter alpha-beta)

Q38. Which factor increases absorption of iron from a meal?

• Phytate-rich cereal intake
• Co-ingestion with vitamin C
• High calcium intake at same meal
• Tea consumption with meal

Correct Answer: Co-ingestion with vitamin C

Q39. Which process explains absorption of vitamin B12?

• Passive diffusion across enterocytes in the jejunum
• Binding to intrinsic factor and receptor-mediated endocytosis in the ileum
• Absorption as micellar complex in the duodenum
• Transport via PEPT1

Correct Answer: Binding to intrinsic factor and receptor-mediated endocytosis in the ileum

Q40. Which transporter is often implicated in efflux of xenobiotics back into the intestinal lumen, reducing absorption?

• PEPT1
• P-glycoprotein (P-gp, MDR1)
• GLUT2
• SGLT1

Correct Answer: P-glycoprotein (P-gp, MDR1)

Q41. Which ion’s absorption is closely coupled with sodium transport in the small intestine?

• Potassium
• Chloride
• Glucose via SGLT1 indirectly couples
• Calcium exclusively

Correct Answer: Glucose via SGLT1 indirectly couples

Q42. How does a high-fat meal typically affect oral absorption of lipophilic drugs?

• Decreases absorption by blocking micelle formation
• Increases absorption by promoting micelle and chylomicron formation
• No effect on lymphatic transport
• Precipitates drugs in gastric acid

Correct Answer: Increases absorption by promoting micelle and chylomicron formation

Q43. Which statement about absorption in the colon is correct?

• The colon is the primary site for nutrient absorption of proteins and carbs
• The colon absorbs water, electrolytes, and some short-chain fatty acids produced by microbiota
• The colon has more villi than the small intestine increasing absorption
• The colon is the main site for bile acid synthesis

Correct Answer: The colon absorbs water, electrolytes, and some short-chain fatty acids produced by microbiota

Q44. Which condition would most likely impair fat absorption?

• Increased bile acid pool
• Pancreatic insufficiency with lack of lipase
• Excessive ileal resection increasing bile recycling
• High dietary fat intake

Correct Answer: Pancreatic insufficiency with lack of lipase

Q45. Which transporter primarily mediates sodium-dependent uptake of certain vitamins like biotin?

• SGLT1
• SMVT (sodium-dependent multivitamin transporter)
• GLUT1
• P-gp

Correct Answer: SMVT (sodium-dependent multivitamin transporter)

Q46. How does inflammation of the intestine (e.g., Crohn’s disease) typically affect drug and nutrient absorption?

• Enhances absorption uniformly
• Can reduce absorption due to mucosal damage, reduced surface area and altered transporters
• Has no effect on absorption
• Only affects lymphatic transport, not portal absorption

Correct Answer: Can reduce absorption due to mucosal damage, reduced surface area and altered transporters

Q47. Which carrier transports many organic anions (e.g., drug conjugates) across enterocytes?

• ASBT
• OATP (organic anion transporting polypeptide)
• GLUT5
• PEPT1

Correct Answer: OATP (organic anion transporting polypeptide)

Q48. Which nutrient absorption is critically dependent on an acidic gastric environment for solubilization?

• Fat-soluble vitamins
• Non-heme iron (Fe2+ availability)
• Vitamin B12 binding to intrinsic factor
• Fructose uptake via GLUT5

Correct Answer: Non-heme iron (Fe2+ availability)

Q49. Which process describes “enteral” absorption?

• Absorption via inhalation route
• Absorption through the gastrointestinal tract (oral to rectal)
• Direct intramuscular injection absorption
• Transdermal absorption

Correct Answer: Absorption through the gastrointestinal tract (oral to rectal)

Q50. Which experimental observation suggests carrier-mediated transport rather than passive diffusion?

• Linear increase of uptake with infinite concentration
• Saturation of uptake at higher substrate concentrations
• Complete independence from temperature
• No stereoselectivity

Correct Answer: Saturation of uptake at higher substrate concentrations

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.

Mail- Sachin@pharmacyfreak.com