Nokea
Which of the following best describes a Gram-negative bacterium?
- A. Has a thick peptidoglycan layer
- B. Has an outer membrane with lipopolysaccharides
- C. Stains purple
- D. Has no cell wall
Correct Answer: B
Rationale: The correct answer is B because Gram-negative bacteria have an outer membrane with lipopolysaccharides, which is a key characteristic used in Gram staining. This outer membrane is responsible for the pink/red color seen when stained with Gram stain. Choice A is incorrect because Gram-negative bacteria have a thin peptidoglycan layer. Choice C is incorrect because Gram-negative bacteria stain pink, not purple. Choice D is incorrect because all bacteria have a cell wall, but Gram-negative bacteria have a different structure compared to Gram-positive bacteria.
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The generic name of a drug refers to its __________ name.
- A. trade
- B. proprietary
- C. chemical
- D. nonproprietary
Correct Answer: D
Rationale: The correct answer is D: nonproprietary. The generic name of a drug is the official, nonproprietary name given to a drug by an organization such as the U.S. Food and Drug Administration (FDA). This name is not owned by any specific company and is used universally to identify the drug's active ingredient. The generic name helps to communicate the specific medication being prescribed and allows for cost-effective options for consumers.
A: Trade name refers to the brand name given to a drug by a pharmaceutical company.
B: Proprietary name is another term for the trade name, specific to the company that produces the drug.
C: Chemical name refers to the exact chemical composition of the drug, which may not be user-friendly or easily recognized by healthcare professionals or consumers.
Risk factor for the development of infection is
- A. malignant disease
- B. cytostatic therapy
- C. premature birth
- D. all of them
Correct Answer: D
Rationale: The correct answer is D: all of them. Malignant disease weakens the immune system, making individuals more susceptible to infections. Cytostatic therapy suppresses the immune system, increasing the risk of infections. Premature birth can lead to underdeveloped immune systems, making babies more prone to infections. Therefore, all three choices are risk factors for the development of infections. Other choices are incorrect because each individual risk factor listed contributes to an increased susceptibility to infections.
Patients after transplantation of allogeneic stem cells are monitored periodically for reactivation of
- A. HAV
- B. CMV
- C. Rubella virus
- D. Measles virus
Correct Answer: B
Rationale: The correct answer is B: CMV. Patients after allogeneic stem cell transplantation are monitored for CMV reactivation due to its potential to cause severe complications in immunocompromised individuals. CMV can lead to organ damage and even mortality in these patients. Monitoring for CMV reactivation allows for early detection and prompt intervention.
Incorrect Choices:
A: HAV - Hepatitis A virus reactivation is not commonly monitored in post-transplant patients.
C: Rubella virus - Rubella is not a common concern for reactivation in this patient population.
D: Measles virus - Measles reactivation is not typically monitored in these patients.
The optimal PH for most pathogenic bacteria and viruses is:
- A. 5.0-5.5
- B. 8.0-9.6
- C. 7.2-7.4
- D. 4.2-4.4
Correct Answer: C
Rationale: The correct answer is C (7.2-7.4) because most pathogenic bacteria and viruses thrive in a neutral pH environment close to 7.0. This pH range is optimal for their growth and survival. Choice A (5.0-5.5) is too acidic for most pathogens. Choice B (8.0-9.6) is too alkaline, which is not conducive for their survival. Choice D (4.2-4.4) is also too acidic and would likely inhibit the growth of pathogenic bacteria and viruses. Thus, a pH range of 7.2-7.4 provides the most suitable conditions for their proliferation.
Bacteria that use oxygen, but only at low concentration, are classified as:
- A. obligate aerobes
- B. microaerophiles
- C. obligate anaerobes
- D. aerotolerant anaerobes
Correct Answer: B
Rationale: The correct answer is B: microaerophiles. These bacteria require oxygen to grow, but only at low concentrations as higher levels can be toxic. They possess enzymes to deal with reactive oxygen species. Obligate aerobes (A) require oxygen for growth, obligate anaerobes (C) cannot survive in the presence of oxygen, and aerotolerant anaerobes (D) can tolerate oxygen but do not use it for growth.