Nokea
What is required for sensitization in contact hypersensitivity?
- A. Antigen-antibody complex formation
- B. T cell presentation of a hapten-modified antigen
- C. Mast cell degranulation
- D. Cytokine suppression
Correct Answer: B
Rationale: The correct answer is B because sensitization in contact hypersensitivity requires T cell presentation of a hapten-modified antigen. This process activates T cells, leading to immune response. Antigen-antibody complex formation (A) is more related to immune responses in humoral immunity. Mast cell degranulation (C) is associated with allergic reactions, not contact hypersensitivity. Cytokine suppression (D) would hinder, not promote, the immune response needed for sensitization in contact hypersensitivity.
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Which definition is the best description of the term genotype?
- A. Basic unit of heredity; arranged on chromosome
- B. Transmission of a disease from parent to child
- C. Genetic identity of an individual not seen as outward characteristics
- D. Family tree containing genetic characteristics and disorders of that family
Correct Answer: C
Rationale: Genotype refers to the genetic makeup of an organism, which may or may not be visible through phenotypic traits.
A nurse has presented an educational program to a community group on Lyme disease. What statement by a participant indicates the need to review the material?
- A. I should take precautions against ticks, especially in the summer.
- B. A red rash that looks like a bull's-eye may be one of the symptoms.
- C. If Lyme disease is not treated successfully, it is usually fatal.
- D. For Stage I disease, antibiotics are usually needed for 14 to 21 days.
Correct Answer: C
Rationale: Step 1: Lyme disease is rarely fatal if treated promptly.
Step 2: Choice C states that Lyme disease is usually fatal if not treated successfully, which is incorrect.
Step 3: Therefore, this statement indicates a need for review as it spreads misinformation.
Step 4: Choices A, B, and D are accurate and align with the information provided in the educational program.
Step 5: In summary, the need to review the material is highlighted by the inaccurate statement in choice C, as the other choices provide correct information on Lyme disease.
L-Selectin is
- A. Expressed on effector T cells
- B. Expressed on HEV
- C. Expressed on naïve T cells
- D. Required to extravasate into tissues
Correct Answer: C
Rationale: The correct answer is C: Expressed on naïve T cells. L-Selectin is a cell adhesion molecule expressed on the surface of naïve T cells. It plays a crucial role in the initial attachment of T cells to high endothelial venules (HEV) in lymphoid tissues, facilitating T cell entry into lymph nodes. It specifically binds to ligands on HEV, allowing T cells to extravasate into lymphoid tissues. Choice A is incorrect because L-Selectin is primarily expressed on naïve T cells rather than effector T cells. Choice B is incorrect as L-Selectin is expressed on HEV, not by them. Choice D is incorrect because L-Selectin is involved in the initial attachment of T cells to endothelial cells, rather than being required for extravasation into tissues.
A patient prescribed corticosteroids for arthritis is surprised to learn of an immune disorder. What should the nurse explain as the reason for the patient not demonstrating typical signs of immune dysfunction?
- A. The arthritis is masking the normal immune response.
- B. The corticosteroids are causing the thymus gland to malfunction.
- C. The arthritis is interfering with the function of immunoglobulins.
- D. Corticosteroids are impacting normal immune response functioning.
Correct Answer: D
Rationale: The correct answer is D because corticosteroids are known to suppress the immune system by inhibiting the production of pro-inflammatory cytokines and preventing the activation of immune cells. This suppression can lead to a decreased immune response, making it less likely for the patient to exhibit typical signs of immune dysfunction.
A: The arthritis masking the immune response is not a plausible explanation as arthritis does not directly affect immune function.
B: Corticosteroids do not cause the thymus gland to malfunction; they mainly impact immune response at the cellular level.
C: Arthritis affecting immunoglobulin function is not a common mechanism of immune dysfunction in this context.
Which of the following is NOT true concerned with Leishmania
- A. It is a unicellular parasite
- B. Proliferates inside phagocytic cells
- C. Transmitted by sand flies
- D. Protection is mainly mediated by IgE
Correct Answer: D
Rationale: The correct answer is D because protection against Leishmania is mainly mediated by cell-mediated immune responses, not IgE antibodies. IgE is not typically involved in protection against intracellular parasites like Leishmania. A: Leishmania is indeed a unicellular parasite. B: Leishmania proliferates inside phagocytic cells, particularly macrophages. C: Leishmania is transmitted by sand flies during blood meals.