Which of the following statements concerning pantothinic acid functions are true:

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: D

Rationale: Rationale: Glucocorticoid hormones affect bone mineral homeostasis by antagonizing vitamin D-stimulated calcium absorption in the intestines, stimulating renal calcium excretion, and increasing parathyroid hormone-induced bone resorption. Therefore, the correct answer is D, as all these mechanisms contribute to the overall impact of glucocorticoids on bone health. Choices A, B, and C alone do not fully capture the multifaceted effects of glucocorticoids on bone mineral homeostasis.

Correct Answer: C

Rationale: The correct answer is C because it presents incorrect information about fluoride. Subjects living in areas with naturally fluoridated water actually have fewer dental caries, not more. This is due to the protective effect of fluoride on teeth. The other choices are correct: A) Fluoride is effective in preventing dental caries by strengthening the enamel, B) Fluoride does accumulate in bones and teeth, enhancing their strength, and D) Chronic exposure to high levels of fluoride can lead to skeletal fluorosis, not just crippling fluorosis. Therefore, C is the only statement that contradicts established facts about fluoride.

Correct Answer: D

Rationale: The correct answer is D - Disolum, Trisolum. These drugs are electrolyte solutions used to control water-salt and acid-base balance. Disolum contains sodium chloride and Trisolum contains sodium bicarbonate, both essential for maintaining electrolyte balance. Option A, B, and C are not directly involved in regulating water-salt and acid-base balance. Polyglucinum is a colloidal solution used for volume replacement, Haemodesum is a plasma substitute, and Glucose isotonic for injections is a source of energy and not specifically for electrolyte balance.

Correct Answer: B

Rationale: Step-by-step rationale: 1. Amphotericin B is known to cause renal impairment and anemia due to its nephrotoxicity and bone marrow suppression. 2. Renal impairment can lead to electrolyte imbalances and decreased kidney function. 3. Anemia can result from bone marrow toxicity, leading to decreased red blood cell production. 4. The other choices (A, C, D) are incorrect as psychosis, hypertension, cardiac arrhythmia, and bone marrow toxicity are not commonly associated with Amphotericin B use. Summary: The correct answer is B because Amphotericin B is most notably known for causing renal impairment and anemia, while the other choices are not typically associated with its unwanted effects.