The exocrine pancreas secretes the following enzymes except:

Correct Answer: C

Rationale: The correct answer is C: Lactase. Lactase is an enzyme produced in the small intestine, not in the pancreas. The exocrine pancreas secretes digestive enzymes like chymotrypsinogen, proelastase, and lipase to aid in the digestion of proteins, fats, and carbohydrates. Lactase is responsible for breaking down lactose, a sugar found in dairy products, and is produced in the small intestine. Therefore, C is the correct answer. Choices A, B, and D are incorrect because chymotrypsinogen, proelastase, and alph are all enzymes produced by the pancreas to aid in digestion.

Correct Answer: C

Rationale: The correct answer is C because carcinoid syndrome can occur with carcinoid tumors of the appendix and ileum. Carcinoid tumors of the appendix can lead to carcinoid syndrome due to the release of serotonin and other vasoactive substances. Similarly, carcinoid tumors localized to the ileum can also produce these substances, leading to the development of carcinoid syndrome. Choices A and B alone are not comprehensive enough as both sites can give rise to carcinoid syndrome. Choice D is incorrect as carcinoid syndrome can indeed occur with tumors from both sites.

Correct Answer: A

Rationale: The correct answer is A. Mass peristalsis refers to the coordinated contraction of the smooth muscle in the colon that helps move fecal matter towards the rectum. This process specifically occurs in the large intestine, not the small intestine. Therefore, choice A is incorrect. Choice B is incorrect because mass peristalsis is actually a rapid and powerful movement, not slow. Choice C is correct as it accurately describes the role of mass peristalsis in facilitating the movement of fecal matter in the large intestine. Choice D is incorrect because choice A is incorrect.

Correct Answer: B

Rationale: The correct answer is B because swallowing is controlled by the swallowing center in the medulla oblongata. This center coordinates the complex sequence of muscle contractions involved in swallowing, ensuring food moves from the mouth to the esophagus without entering the airway. The pharyngeal phase is actually involuntary, not voluntary (Choice A). Swallowing usually occurs with a closed mouth, not an open one (Choice C). Additionally, the buccal phase is not accompanied by apnea; breathing typically continues during this phase (Choice D). Therefore, the correct answer is B due to the central control of swallowing in the medulla oblongata.

Correct Answer: A

Rationale: The correct answer is A: Emulsify fats. Bile emulsifies fats by breaking them down into smaller droplets, increasing the surface area for enzymes to work on, aiding in the digestion and absorption of fats. Choices B and C are incorrect as bile specifically targets fats, not proteins or carbohydrates. Choice D is incorrect as bile plays a crucial role in fat digestion.