Nokea
Mycoplasma species lack:
- A. Cell wall
- B. Plasma membrane
- C. DNA
- D. Ribosomes
Correct Answer: A
Rationale: The correct answer is A: Cell wall. Mycoplasma species lack a cell wall, making them unique among bacteria. This is because they have a flexible cell membrane that provides structural support instead of a rigid cell wall. The absence of a cell wall allows them to be pleomorphic and gives them resistance to certain antibiotics targeting cell wall synthesis. Plasma membrane (B), DNA (C), and ribosomes (D) are present in Mycoplasma species, so they are not the correct answer.
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What is the best therapeutic plan for treating actinomycosis?
- A. Awaiting self-clearance
- B. Only antibiotic therapy
- C. Only surgical treatment
- D. Chemotherapy combined with surgical therapy
Correct Answer: D
Rationale: The correct answer is D, chemotherapy combined with surgical therapy. Actinomycosis is a bacterial infection that requires a combination of antibiotics to target the bacteria and surgery to remove abscesses or infected tissues. Antibiotics alone may not penetrate abscesses effectively. Waiting for self-clearance can lead to complications. Surgical treatment alone may not eradicate the infection entirely. Therefore, the most effective therapeutic plan is to combine chemotherapy to treat the infection systemically and surgery to remove localized infections.
The cleaning of glassware and tableware in restaurants falls into the category of
- A. degermation.
- B. sterilization.
- C. disinfection.
- D. sanitization.
Correct Answer: D
Rationale: The correct answer is D: sanitization. Sanitization is the process of reducing the number of microorganisms on surfaces to a safe level. In restaurants, cleaning glassware and tableware aims to eliminate harmful bacteria to prevent foodborne illnesses. Degermation (A) focuses on removing germs from a specific area, sterilization (B) eliminates all microorganisms, and disinfection (C) reduces the number of pathogens but may not completely eliminate them, making them less effective choices for this context.
Which description matches most to adenoviruses:
- A. Middle sized, naked icosahedral capsid, double-stranded DNA
- B. Small-sized, enveloped capsid, ssRNA
- C. Large, enveloped capsid, double stranded DNA
- D. None of the above
Correct Answer: A
Rationale: Step-by-step rationale:
1. Adenoviruses are DNA viruses, so choices B and C (ssRNA and DNA) are incorrect.
2. Adenoviruses have a middle-sized, naked icosahedral capsid, making choice A the correct description.
3. Choice D is incorrect as adenoviruses do have specific characteristics, making "None of the above" an inaccurate option.
In summary, the correct answer A is supported by the fact that adenoviruses have a middle-sized, naked icosahedral capsid and contain double-stranded DNA. Choices B, C, and D are incorrect as they do not align with the characteristics of adenoviruses.
Sterilization is a process that:
- A. Destroys most microorganism, but spores remain viable
- B. Leads to complete destruction of all microorganisms, including resistant forms such as spores
- C. Reduces the number of microorganisms on the surface of the skin
- D. None of the above
Correct Answer: B
Rationale: The correct answer is B because sterilization is the process of completely destroying all microorganisms, including resistant forms like spores, ensuring no viable organisms remain. This is crucial for ensuring complete elimination of potential pathogens. Choice A is incorrect because sterilization should eliminate all microorganisms, including spores. Choice C is incorrect as it describes disinfection, not sterilization. Choice D is incorrect because sterilization aims to eradicate all microorganisms, not leave any viable ones behind.
A 16-year-old adolescent was vaccinated with DTP. In eight days there was stiffness and pain in the joints, subfebrile temperature, urticarial skin eruption, enlargement of inguinal, cervical lymph nodes and spleen. What kind of allergic reaction is observed?
- A. Immunocomplex
- B. Hypersensitivity of immediate type
- C. Cytoxic
- D. Hypersensitivity of delayed type
Correct Answer: D
Rationale: The correct answer is D: Hypersensitivity of delayed type. The symptoms described occur 5-10 days after exposure to the antigen, consistent with a delayed hypersensitivity reaction. This type of reaction involves T cells and is characterized by cell-mediated immune response, leading to inflammation and tissue damage. Choices A, B, and C are incorrect because they are associated with different mechanisms of allergic reactions. Immunocomplex reactions (choice A) involve antigen-antibody complexes depositing in tissues, immediate hypersensitivity reactions (choice B) involve IgE-mediated mast cell degranulation, and cytotoxic reactions (choice C) involve antibodies targeting specific cells for destruction.