The functional unit of the kidney is the nephron. A nephron is made up of renal tubules and renal corpuscles, both of which perform different functions. Which of the following parts of the nephron is not correctly paired with its function?

Correct Answer: B

Rationale: The correct answer is B: Collecting Ducts - Secretion of water. Collecting ducts are responsible for reabsorption of water, not secretion. The other choices are correctly paired: A) Glomerulus filters blood, C) Loop of Henle reabsorbs water, D) Proximal Convoluted Tubules reabsorb ions and solutes. Collecting ducts play a crucial role in concentrating urine by reabsorbing water under the influence of hormones like ADH.

Correct Answer: C

Rationale: Step-by-step rationale: 1. Fluconazole is preferred due to its efficacy, safety, and tolerability in Cryptococcal meningitis. 2. It has better CNS penetration compared to other azoles. 3. It is less toxic than Amphotericin B and Flucytosine. 4. Ketoconazole is less effective and not recommended for this indication. Summary: - A: Amphotericin B is reserved for severe cases due to its toxicity. - B: Flucytosine is used in combination therapy but not as the primary drug of choice. - D: Ketoconazole is less effective and not preferred for Cryptococcal meningitis in AIDS patients.

Correct Answer: A

Rationale: The correct answer is A: Vancomycin. Red man syndrome is a type of hypersensitivity reaction associated with rapid intravenous infusion of vancomycin. This is due to the release of histamine from mast cells and basophils. Vancomycin is known to cause this syndrome, while the other antibiotics listed do not have a similar association. Clindamycin is more commonly associated with pseudomembranous colitis, Cefoperazone with liver toxicity, and Piperacillin with hypersensitivity reactions like rash or anaphylaxis. Therefore, based on the mechanism of action and clinical evidence, vancomycin is the correct choice for causing red man syndrome.

Correct Answer: A

Rationale: The correct answer is A: Dapsone. Dapsone is known to cause hemolysis in patients with G6PD deficiency due to oxidative stress. G6PD deficiency leads to reduced ability to protect red blood cells from oxidative damage, which can be exacerbated by drugs like dapsone. Rifampicin and clofazimine are not associated with hemolysis in G6PD deficient patients. Option D is incorrect as dapsone is known to cause hemolysis in this population.

Correct Answer: D

Rationale: The correct answer is D: Clindamycin. Clindamycin is associated with the highest incidence of antibiotic-associated pseudomembranous enterocolitis due to its broad-spectrum activity that disrupts the normal gut flora, leading to overgrowth of Clostridium difficile. Ampicillin, Chloramphenicol, and Vancomycin are also associated with pseudomembranous enterocolitis, but the highest incidence is seen with Clindamycin due to its stronger impact on gut flora imbalance.