Which of these enzymes is responsible for the digestion of lipids?

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: 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.

Correct Answer: C

Rationale: The correct answer is C: small intestine. Primary carcinoma is least common in the small intestine due to its relatively lower exposure to carcinogens and slower cellular turnover compared to other segments like the colon. The esophagus is prone to carcinoma due to chronic irritation from acid reflux. The stomach is susceptible due to factors like Helicobacter pylori infection and dietary habits. The colon is at higher risk due to frequent exposure to fecal carcinogens. In summary, the small intestine has the least incidence of primary carcinoma due to lower exposure to risk factors.

Correct Answer: D

Rationale: The correct answer is D: Amylase. Gastric secretion does not contain amylase. Amylase is an enzyme produced by the pancreas and salivary glands to break down carbohydrates. In the stomach, gastric secretions mainly consist of hydrochloric acid (HCl) for digestion, intrinsic factor (IF) for vitamin B12 absorption, and mucous to protect the stomach lining. Therefore, amylase is not a component of gastric secretion.