Hormones are:

Correct Answer: A

Rationale: The correct answer is A because hormones are indeed products of endocrine gland secretion. Endocrine glands release hormones directly into the bloodstream to regulate various physiological processes. Choice B is incorrect as hormones are not mediators of the inflammatory process. Choice C is wrong because hormones are not by-products of tissue metabolism but rather specific signaling molecules. Choice D is incorrect as hormones are not products of exocrine gland secretion but rather endocrine glands.

Correct Answer: D

Rationale: Rationale: Glucocorticoids are indicated for a wide range of conditions due to their anti-inflammatory and immunosuppressive effects. A: Glucocorticoids are used in both chronic (Addison's disease) and acute adrenocortical insufficiency to replace deficient cortisol levels. B: Glucocorticoids are essential for preventing rejection in organ transplant recipients by suppressing the immune response. C: Glucocorticoids are effective in managing inflammatory conditions of bones and joints by reducing inflammation and pain. Therefore, the correct answer is D because glucocorticoids are indicated for all the mentioned conditions due to their diverse mechanisms of action.

Correct Answer: D

Rationale: The correct answer is D. Glucocorticoids exert their immunosuppressive effect through multiple mechanisms. A: Glucocorticoids reduce lymphocyte (T and B cells) concentration and inhibit the function of tissue macrophages and other antigen-presenting cells, leading to decreased immune response. B: Glucocorticoids suppress cyclooxygenase II expression, reducing prostaglandin synthesis, which is involved in inflammation. C: Glucocorticoids activate phospholipase A2, reducing prostaglandin and leukotriene synthesis, further dampening the immune response. Therefore, all of the choices (A, B, and C) contribute to the immunosuppressive effect of glucocorticoids.

Correct Answer: B

Rationale: Rationale for choice B being correct: 1. Pantothenic acid is an essential constituent of coenzyme A (CoA). 2. Coenzyme A is crucial for acyl transfer in the TCA cycle and de novo fatty acid synthesis. 3. De novo fatty acid synthesis requires CoA for the activation and transport of acyl groups. 4. Without pantothenic acid, CoA cannot function properly in these metabolic processes. Summary of why other choices are incorrect: A: Pyridoxal phosphate is the active form of vitamin B6, not pantothenic acid. It is involved in amino acid metabolism, not pantothenic acid. C: Pantothenic acid is not primarily known for its antioxidant properties; its main role is as a precursor for CoA. D: The described reactions involve other coenzymes like biotin and vitamin B12, not pantothenic acid.

Correct Answer: A

Rationale: The correct answer is A: TRUE. Clofibrate is the drug of choice for type III hyperlipidemia due to its ability to reduce triglyceride levels. Other choices (B, C, D) are incorrect because they do not accurately reflect the specific drug recommended for type III hyperlipidemia. Choice B is incorrect as clofibrate is indeed the preferred drug for this condition. Choice C is incorrect as not all options are valid in this context. Choice D is incorrect as there is a specific drug recommended for type III hyperlipidemia.