The white pulp and red pulp are part of which immune organ:

Correct Answer: C

Rationale: The correct answer is C: Spleen. The white pulp of the spleen contains lymphocytes that help in immune responses. The red pulp filters blood and removes old or damaged red blood cells. The thymus (A) is responsible for T cell maturation, lymph nodes (B) filter lymph, and lymphoid tissue (D) includes various lymphoid organs but does not specifically refer to the spleen's distinct white and red pulp structure. Thus, the spleen is the only organ among the choices that has both white and red pulp components essential for immune functions.

Correct Answer: A

Rationale: The correct answer is A: Mantoux test. The Mantoux test is used to screen for tuberculosis by injecting PPD intradermally. The presence of a delayed hypersensitivity reaction indicates prior exposure to Mycobacterium tuberculosis. The Schick test (B) is used to test for immunity to diphtheria, while the Dick test (C) is used to test for immunity to scarlet fever. Therefore, the correct use of PPD is in the Mantoux test for tuberculosis screening.

Correct Answer: C

Rationale: The correct answer is C: Anti-measles IgM. During acute measles infection, the body produces IgM antibodies specific to the measles virus. This indicates a recent or current infection. A: Anti-mumps IgM and B: Anti-rubella IgM are specific to mumps and rubella viruses, respectively, not measles. D: Anti-CMV IgM is specific to cytomegalovirus, not measles. In summary, choice C is correct because Anti-measles IgM is the specific antibody indicating acute measles infection, while the other choices are antibodies related to different viruses.

Correct Answer: D

Rationale: Production of auto-antibodies can be due to various factors. Mutant B cell clones can lead to the production of self-reactive antibodies. Antibodies against hidden tissues can also trigger autoimmune responses. Genetic factors play a crucial role in predisposing individuals to autoimmunity. Therefore, the correct answer is D, as all these factors can contribute to the production of auto-antibodies. Choice A is incorrect as it only addresses one possible cause. Choice B is incorrect as it focuses solely on antibodies against hidden tissues. Choice C is incorrect as it overlooks the other potential reasons for auto-antibody production.

Correct Answer: A

Rationale: The correct answer is A: Isoniazid and rifampicin. These drugs are considered first-line treatment for tuberculosis due to their high efficacy and low toxicity. Isoniazid targets the cell wall of the tuberculosis bacteria, while rifampicin inhibits RNA synthesis. They are recommended by WHO as the first choice for treating tuberculosis. Choice B (Penicillin and erythromycin) is incorrect because these antibiotics are not effective against tuberculosis bacteria. Choice C (Trimethoprim and third generation cephalosporins) is incorrect because they are not considered first-line drugs for tuberculosis treatment. Choice D (All the listed above can be used depending on their resistance profile) is incorrect because only isoniazid and rifampicin are universally recognized as first-line drugs for tuberculosis regardless of resistance profile.