Which condition may benefit from branched chain amino acids (leucine, isoleucine, and valine)?

Correct Answer: A

Rationale: Branched chain amino acids, such as leucine, isoleucine, and valine, are essential in preventing muscle breakdown. Therefore, they may be particularly important for a patient with cancer-related malnutrition, where maintaining muscle mass is crucial. Marasmus is a severe form of malnutrition characterized by energy deficiency, not specifically related to cancer. Cardiovascular disease and severe depression do not have a direct correlation with the need for branched chain amino acids to prevent muscle breakdown.

Correct Answer: B

Rationale: Pepsinogen is converted into its active form, pepsin, by hydrochloric acid in the stomach. Hydrochloric acid helps in unfolding the pepsinogen molecule to transform it into pepsin, which is crucial for protein digestion. Therefore, the correct answer is hydrochloric acid (choice B). Enterokinase (choice A) is an enzyme produced in the small intestine that activates trypsinogen into trypsin, not pepsinogen. Gastric lipase (choice C) is an enzyme that digests fats, not involved in converting pepsinogen to pepsin. Pancreatic lipase (choice D) is an enzyme produced by the pancreas that aids in breaking down fats in the small intestine, not part of the process of pepsin activation.

Correct Answer: D

Rationale: The correct answer is D, rennin. Rennin is the enzyme in infants responsible for coagulating milk, which aids in the digestion process. Choice A, casein, is a milk protein and not an enzyme. Choices B and C, pepsinogen and trypsin, are digestive enzymes but are not specifically involved in coagulating milk in infants.

Correct Answer: D

Rationale: The correct answer is D: By enterokinase. Trypsin is activated by enterokinase, an enzyme secreted by the small intestine. Enterokinase plays a crucial role in converting trypsinogen into its active form, trypsin. Choices A, B, and C are incorrect because trypsin is specifically activated by enterokinase, not by zymogen, bile, or gastrin.

Correct Answer: C

Rationale: Chymotrypsin is an enzyme found in pancreatic secretions that plays a role in protein digestion. Rennin is primarily found in the stomach and is involved in milk digestion. Pepsin is also a stomach enzyme that aids in protein breakdown. Casein is a protein found in milk, not an enzyme involved in pancreatic secretions. Therefore, the correct answer is Chymotrypsin.