Compared to primary immune response the secondary immune response
- A. 1. Is quicker
- B. 2. Produces much more antibodies
- C. 3. Requires more antigen stimulations
- D. 4. Is slower
Correct Answer: A
Rationale: The correct answer is A because the secondary immune response is quicker due to memory B and T cells being already present from the primary response. These memory cells can quickly recognize and respond to the antigen upon re-exposure, leading to a faster and more efficient immune response. Choices B and C are incorrect as the secondary response produces more antibodies and requires fewer antigen stimulations. Choice D is also incorrect as the secondary response is faster than the primary response.
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The sample used to proving epidemic meningitis is:
- A. CSF transported at 37°C (CSF sample, blood, nasopharyngeal secretion)
- B. Feces
- C. CSF transported at +4°C
- D. None of the above
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.
A Gram-stained smear from a wound revealed Gram-positive rods with terminal spores. The bacteria were anaerobic and produced gas. What is the most likely causative agent?
- A. Clostridium perfringens
- B. Bacillus anthracis
- C. Clostridium botulinum
- D. Clostridium tetani
Correct Answer: A
Rationale: The correct answer is A: Clostridium perfringens. This bacterium is an anaerobic, Gram-positive rod that forms terminal spores and produces gas. It is commonly associated with wound infections and gas gangrene. Clostridium botulinum causes botulism and does not typically present with gas production. Bacillus anthracis is an aerobic, Gram-positive spore-forming bacterium causing anthrax. Clostridium tetani causes tetanus and does not produce gas. Thus, based on the characteristics described in the question, Clostridium perfringens is the most likely causative agent.
Medical examination of the first-year pupils included Mantoux test. 15 pupils out of 35 had negative reaction. What actions should be taken against children with negative reaction?
- A. BCG vaccination
- B. Antitoxin vaccination
- C. Rabies vaccination
- D. Repeat Mantoux test
Correct Answer: A
Rationale: The correct answer is A: BCG vaccination. The Mantoux test is used to detect tuberculosis infection. A negative reaction means the child is not infected. BCG vaccination is recommended for individuals without prior TB infection to prevent severe forms of the disease. Antitoxin and rabies vaccinations are not related to TB and are not indicated in this scenario. Repeating the Mantoux test is unnecessary since a negative result indicates absence of TB infection.
During bacteriological examination of the purulent discharge obtained from a postoperative wound an inoculation on meat infusion agar has been performed. The inoculation has resulted in large colorless mucous colonies that in 24 hours with exposure to sunlight developed green-blue pigmentation and smell of honey or jasmine. Bacterioscopy revealed gram-negative lophotrichea. What bacterial culture is contained in purulent discharge?
- A. Pseudomonas aeruginosa
- B. Proteus vulgaris
- C. Klebsiella osaenae
- D. Streptomyces griseus
Correct Answer: A
Rationale: The correct answer is A: Pseudomonas aeruginosa. Pseudomonas aeruginosa is a gram-negative bacterium known for its green-blue pigmentation and sweet, fruity odor. The large colorless mucous colonies that develop green-blue pigmentation and honey or jasmine smell point towards Pseudomonas aeruginosa. The bacterioscopy revealing gram-negative lophotrichea further supports this identification. Proteus vulgaris and Klebsiella osaenae do not typically exhibit the described characteristics. Streptomyces griseus is a soil bacterium known for its antibiotic production and is not commonly associated with wound infections.
Bacteria are studied by:
- A. Taxonomy
- B. Classification
- C. Identification
- D. Nomenclature
Correct Answer: C
Rationale: The correct answer is C: Identification. Bacteria are studied by identification to determine their specific characteristics and differentiate between different species. Taxonomy (A) is the science of classification, not specific to bacteria. Classification (B) is the process of grouping organisms based on shared characteristics, not specific to bacteria. Nomenclature (D) is the naming system for organisms, not the primary method for studying bacteria. Therefore, identification (C) is the correct choice for studying bacteria.