What is the role of the villi in the small intestine?

Correct Answer: B

Rationale: The correct answer is B: absorbing nutrients. Villi are finger-like projections in the small intestine that increase surface area for absorption of nutrients. They contain blood vessels and lacteals that absorb nutrients like glucose and amino acids. Villi do not secrete digestive enzymes (choice A), produce bile (choice C), or produce mucus (choice D). Digestive enzymes are produced by the pancreas and bile is produced by the liver. Mucus is produced by goblet cells in the intestine.

Correct Answer: C

Rationale: The correct answer is C: Lipase. Lipase is responsible for the digestion of lipids because it breaks down fats into fatty acids and glycerol. Amylase (A) digests carbohydrates, Pepsin (B) digests proteins, and Trypsin (D) also digests proteins but in the small intestine. Lipase is the only enzyme that specifically targets lipids for digestion, making it the correct choice in this scenario.

Correct Answer: A

Rationale: The correct answer is A: Hyperglycemia. GIP (gastric inhibitory polypeptide) is released in response to food intake to stimulate insulin release and inhibit glucagon secretion, leading to reduced blood glucose levels. Excessive GIP production from a tumor can result in excessive insulin release, causing hypoglycemia. This is why the correct answer is hyperglycemia. Choices B, C, and D are incorrect as they do not align with the physiological effects of GIP.

Correct Answer: C

Rationale: The correct answer is C because if the oesophageal muscles are not working, dysphagia to solids and liquids would occur. This is because the muscles are responsible for peristalsis, which is the wave-like contractions that push food down the esophagus. Choice A is incorrect because gravity alone cannot compensate for muscle dysfunction. Choice B is incorrect as water swallowing also requires proper muscle function. Choice D is incorrect as vomiting is not directly related to oesophageal muscle dysfunction.

Correct Answer: B

Rationale: The correct answer is B because a filling defect on a barium examination indicates that something is protruding into the lumen, displacing the barium. This means there is an abnormality or mass present that prevents the barium from flowing uniformly. Choice A is incorrect because a filling defect does not necessarily indicate local dilation or outpouching. Choice C is incorrect because it combines both A and B, which is not always the case. Choice D is incorrect as there is indeed something causing the barium to be displaced in the lumen.