Nokea
Why do we constantly need new flu vaccines?
- A. Because flu viruses mutate frequently due to their error-prone RNA polymerase
- B. Because completely new variants can be created from an assortment of previously circulating strains due the segmented nature of the viral genome
- C. Because antibodies generated in vaccinated people are short-lived and need to be generated again with a new vaccine injection
- D. Both A and B are correct
Correct Answer: D
Rationale: The correct answer is D. Choice A is correct because flu viruses mutate frequently due to their error-prone RNA polymerase, leading to new strains. Choice B is correct because the segmented nature of the viral genome allows for reassortment of different strains, creating completely new variants. Therefore, new vaccines are needed to target these evolving strains. Choice C is incorrect as the need for new vaccines is primarily driven by the genetic variability of the virus, not solely by the short-lived nature of antibodies. Thus, choices A and B together provide a comprehensive explanation for the constant need for new flu vaccines.
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Colostrum, the yellowish fluid, secreted by mother during the initial days of lactation is very essential to impart immunity to the newborn infants because it contains:
- A. Natural killer cells
- B. Monocytes
- C. Macrophages
- D. Immunoglobulin A
Correct Answer: D
Rationale: The correct answer is D: Immunoglobulin A. Colostrum contains high levels of Immunoglobulin A (IgA), which is crucial for imparting passive immunity to the newborn. IgA helps protect the infant's mucosal surfaces from infections. Natural killer cells, monocytes, and macrophages are not typically found in colostrum and are not responsible for conferring immunity to the newborn.
A patient with advanced AIDS has a nursing diagnosis of impaired memory related to neurologic changes. In planning care for the patient, what should the nurse set as the highest priority?
- A. Maintain a safe patient environment
- B. Provide a quiet, nonstressful environment to avoid overstimulation
- C. Use memory cues such as calendars and clocks to promote orientation
- D. Provide written instructions of directions to promote understanding and orientation
Correct Answer: A
Rationale: Safety is paramount for cognitively impaired patients. Preventing falls and ensuring access to necessities takes precedence over other interventions.
The three antibiotic-resistant bacteria that are of most current concern in North America are ____________________, ____________________, and ____________________.
- A. Methicillin-resistant Staphylococcus aureus (MRSA)
- B. Carbapenem-resistant Enterobacteriaceae (CRE)
- C. Vancomycin-resistant Enterococcus (VRE)
- D. All of the above
Correct Answer: D
Rationale: The correct answer is all of the above. MRSA, CRE, and VRE are among the most concerning antibiotic-resistant bacteria in North America due to their prevalence and difficulty in treatment.
Secondary lymphoid tissues are where:
- A. naïve lymphocytes become activated
- B. VDI gene rearrangement occurs
- C. Somatic hypermutation occurs
- D. Two of these options are correct
Correct Answer: D
Rationale: The correct answer is D because secondary lymphoid tissues are where both A and C processes occur. Naïve lymphocytes become activated in secondary lymphoid tissues through interactions with antigens, leading to their differentiation into effector cells. Somatic hypermutation also occurs in secondary lymphoid tissues, specifically in germinal centers of lymph nodes, leading to the generation of high-affinity antibodies. Option B, VDI gene rearrangement, does not occur in secondary lymphoid tissues; it is a process that happens in the primary lymphoid organs (bone marrow and thymus) during the development of lymphocytes. Thus, options A and C are correct, making the correct answer D.
Lysozyme is NOT
- A. An enzyme present in secretions and tears
- B. A type of Defensin
- C. Part of the chemical innate barriers to infection
- D. A protein capable of dissolving the cell wall of bacteria
Correct Answer: B
Rationale: The correct answer is B because lysozyme is not a type of defensin. Lysozyme is an enzyme present in secretions and tears, part of chemical innate barriers to infection, and capable of dissolving the cell wall of bacteria. Defensins are a different type of antimicrobial peptides that function by disrupting the microbial cell membrane. Therefore, B is the correct answer as it does not accurately describe lysozyme's function.