What clinical specimen can be analysed in the diagnosis of sexually transmitted infections:

Correct Answer: D

Rationale: Certainly! The correct answer is D because all three options (A, B, and C) can be analyzed in the diagnosis of sexually transmitted infections. Genital ulcer secretions can reveal the presence of pathogens causing STIs, lymph node punctate can indicate systemic infection, and serum can be tested for specific STI antibodies. Therefore, all these clinical specimens are essential for a comprehensive diagnosis of sexually transmitted infections. The other choices (A, B, C) are incorrect as they individually represent important specimens used in the diagnosis process.

Correct Answer: D

Rationale: The correct answer is D (A and B both). In viral multiplication, the presence of a specific cytopathic effect (CPE) in cell culture indicates viral replication. This is detected visually through changes in cell morphology. Additionally, immunofluorescence detection methods can be used to detect viral antigens within infected cells, confirming viral multiplication. Options C is incorrect as viral colonies are not typically used to detect viral multiplication in cell culture. Option B alone is not sufficient as it only focuses on immunofluorescence detection, while option A alone may not always be specific. Therefore, the combination of A and B provides a more comprehensive and accurate detection method for viral multiplication in cell culture.

Correct Answer: A

Rationale: The correct answer is A: Anatoxin. An anatoxin is a preparation that contains inactivated toxins produced by the anthrax-causing bacteria. By administering anatoxin, the population can develop immunity against the toxin without being exposed to the live bacteria. This specific prophylaxis approach helps prevent the development of anthrax infection by targeting the toxin itself. Summary: - Choice B (Inactivated vaccine) is incorrect because an inactivated vaccine typically contains killed or inactivated whole bacteria, not just the toxins. - Choice C (Chemical vaccine) is incorrect as there is no such thing as a chemical vaccine; vaccines are biological preparations. - Choice D (Genetically engineered vaccine) is incorrect because while vaccines can be genetically engineered, the specific term "genetically engineered vaccine" does not accurately describe the prophylaxis used against anthrax in this scenario.

Correct Answer: B

Rationale: The primary function of bacterial capsules is to aid in adhesion and protect against phagocytosis. Capsules help bacteria adhere to surfaces and evade immune system detection by preventing phagocytosis. This is important for bacterial survival and colonization in host organisms. Choice A, protein synthesis, is incorrect as capsules do not directly participate in this process. Choice C, facilitate motility, is incorrect as capsules are not involved in bacterial movement. Choice D, synthesize DNA, is incorrect as capsules do not have a role in DNA synthesis. Thus, the correct answer is B.

Correct Answer: A

Rationale: The correct answer is A: Sabouraud's peptone agar. This agar is specifically designed for the isolation of yeast and molds due to its low pH and high sugar content, creating an environment conducive for their growth. Yeast-like fungi thrive in this selective medium, while inhibiting the growth of bacteria and other contaminants. Summary: - Sabouraud's peptone agar is ideal for cultivating yeast-like fungi. - Endo agar is used for isolation of gram-negative bacteria, not fungi. - Milk-salt agar is used for lactobacilli and streptococci, not fungi. - Meat infusion agar is a general-purpose medium for cultivation of a wide range of microorganisms, not specifically for yeast-like fungi.