microbiology an introduction test bank

Correct Answer: A

Rationale: The correct answer is A because CSF (Cerebrospinal fluid) is the sample used for proving epidemic meningitis. It should be transported at 37�C to maintain its integrity. Blood and nasopharyngeal secretions are not typically used for diagnosing meningitis. Choice B, feces, is unrelated to the diagnosis of meningitis. Choice C, CSF transported at +4�C, is incorrect as it should be transported at 37�C to prevent degradation of the sample. Therefore, A is the correct choice for proving epidemic meningitis due to the specificity of the sample and the proper transport conditions.

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.

Correct Answer: D

Rationale: The correct answer is D, "All of the above." Bacterial meningitis can be caused by Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae. These bacteria are common pathogens associated with meningitis. Each of them can lead to serious infections in the brain and spinal cord. Neisseria meningitidis is known for causing meningococcal meningitis, Haemophilus influenzae is a common cause of H. influenzae meningitis, and Streptococcus pneumoniae is responsible for pneumococcal meningitis. Therefore, since all three bacteria can cause bacterial meningitis, the correct answer is D. Choices A, B, and C are incorrect because each of these bacteria individually can cause bacterial meningitis; it is not limited to just one specific type.

Correct Answer: B

Rationale: The correct answer is B because reinfection is indeed possible with rabies virus. Step 1: Reinfection occurs if a person is exposed to the virus again after initial infection. Step 2: Once infected, the virus can remain dormant in the body and become active upon re-exposure. Step 3: Therefore, it is essential to continue preventive measures even after initial immunization. Summary: Choices A, C, and D are incorrect because antibodies develop within 14-15 days post-immunization, HRIG is administered shortly after exposure, and a specific vaccination schedule is followed for rabies prophylaxis, respectively.

Correct Answer: B

Rationale: The correct answer is B: Actinomycosis. Actinomyces is a gram-positive bacterium that forms sulfur granules (druses) with gram-positive coloring in the center and filamentous structures resembling cones with gram-negative coloring. This morphology is characteristic of Actinomyces species. Fusobacteriosis (choice A) typically presents with gram-negative rods. Staphylococcal osteomyelitis (choice C) is caused by gram-positive staphylococci, not Actinomyces. Anaerobic infections (choice D) can be caused by various bacteria, but the specific morphology described in the question matches Actinomyces, making choice B the correct answer.