Digestion MCQs set 2 for AKU Entry Test Biology — 20 solved questions.
Q1. A patient with pancreatic insufficiency is unable to digest fats properly. Which enzyme is responsible for fat digestion?
Answer: Lipase
Explanation: Lipase breaks down fats; Amylase is for carbohydrates, Trypsin and Pepsin are proteases.
Q2. A person with lactose intolerance lacks the enzyme lactase in their small intestine. What is the primary function of lactase?
Answer: Breaking down lactose into glucose and galactose
Explanation: Lactase splits lactose into glucose and galactose; other enzymes handle proteins, starch, and fats.
Q3. Gastric juice contains hydrochloric acid (HCl), which activates pepsinogen to pepsin. What is the role of pepsin in protein digestion?
Answer: Breaking down proteins into smaller peptides
Explanation: Pepsin breaks proteins into smaller peptides; other enzymes complete breakdown to amino acids.
Q4. A 45-year-old man is diagnosed with a condition where the lower esophageal sphincter (LES) is not functioning properly. What is the likely consequence?
Answer: Gastric contents refluxing into the esophagus
Explanation: LES prevents gastric reflux; its failure allows stomach contents to reflux into the esophagus.
Q5. Bile salts emulsify fats, making them easier for lipase to digest. Where are bile salts produced?
Answer: Liver
Explanation: Bile salts are produced in the liver; stored in the gallbladder, released into the small intestine.
Q6. A patient with celiac disease has an immune reaction to gluten, damaging the villi of their small intestine. What is the primary consequence of this damage?
Answer: Reduced surface area for absorption
Explanation: Damaged villi reduce the surface area for nutrient absorption; not enhancing absorption or enzyme secretion.
Q7. The hormone cholecystokinin (CCK) stimulates the gallbladder to release bile. What else does CCK stimulate?
Answer: Release of pancreatic juice rich in enzymes
Explanation: CCK stimulates the pancreas to release enzyme-rich juice; not directly related to gastric juice or pancreatic hormones.
Q8. The enteric nervous system can function without input from the CNS, regulating digestive processes. What is this ability called?
Answer: Local control
Explanation: Local control refers to the enteric nervous system's ability to regulate digestion without CNS input.
Q9. A person consumes a meal high in triglycerides. Where are these triglycerides primarily digested?
Answer: Small intestine
Explanation: Triglycerides are mainly digested in the small intestine by lipase; some gastric lipase action in the stomach.
Q10. The presence of fatty acids in the duodenum stimulates the release of which hormone?
Answer: CCK
Explanation: CCK is released in response to fatty acids in the duodenum; Secretin is released due to acidic chyme.
Q11. The brush border enzymes of the small intestine include sucrase, lactase, and maltase. What do these enzymes have in common?
Answer: They digest carbohydrates into simple sugars
Explanation: These enzymes break down disaccharides into simple sugars; not related to protein or fat digestion.
Q12. Gastrin is a hormone that stimulates the secretion of gastric juice. Where is gastrin produced?
Answer: Stomach
Explanation: Gastrin is produced in the G cells of the stomach lining; stimulates gastric secretion.
Q13. The migrating motor complex (MMC) is a pattern of electromechanical activity observed in the gastrointestinal tract during fasting. What is its role?
Answer: Clearing residual contents from the stomach and small intestine
Explanation: MMC clears residual contents during fasting; not directly related to absorption, enzyme secretion, or blood flow.
Q14. A 30-year-old woman has a condition where her pancreas is not producing enough bicarbonate. What is the likely effect on her digestive system?
Answer: Failure to neutralize acidic chyme
Explanation: Bicarbonate neutralizes acidic chyme; its deficiency impairs this neutralization, not directly affecting pepsin or bile.
Q15. The small intestine has a large surface area due to the presence of villi and microvilli. What is the main advantage of this large surface area?
Answer: Improved absorption of nutrients
Explanation: Large surface area enhances nutrient absorption; not directly related to enzyme secretion, food mixing, or storage.
Q16. Secretin is a hormone released by the duodenum in response to acidic chyme. What is its primary effect?
Answer: Stimulating the release of pancreatic juice rich in bicarbonate
Explanation: Secretin stimulates the pancreas to release bicarbonate-rich juice to neutralize acidic chyme.
Q17. The enzyme enteropeptidase (also known as enterokinase) is located on the brush border of the small intestine. What is its role?
Answer: Activating trypsinogen to trypsin
Explanation: Enteropeptidase activates trypsinogen to trypsin; trypsin then activates other pancreatic enzymes.
Q18. A patient is diagnosed with a condition that results in the inability to absorb fat-soluble vitamins. Which part of the digestive system is most likely affected?
Answer: Small intestine
Explanation: The small intestine is responsible for absorbing fat-soluble vitamins; liver and pancreas aid in digestion but aren't the primary site.
Q19. The process of peristalsis helps move food through the digestive tract. Where is peristalsis most effective?
Answer: Esophagus
Explanation: Peristalsis is most effective in the esophagus; it propels food into the stomach.
Q20. A 25-year-old man has a condition that results in excessive secretion of gastric acid. What is a likely consequence?
Answer: Peptic ulcer disease
Explanation: Excessive gastric acid can lead to peptic ulcer disease; not directly related to nutrient absorption or infection risk.