Nokea
When a B-cell undergoes immunoglobulin class switching
- A. the variable region of the light chain changes, but its constant region remains the same
- B. the variable region of the light chain remains the same, but its constant region changes
- C. the variable region of the heavy chain remains the same but its constant region changes
- D. the variable region of the heavy chain changes but its constant region remains the same
Correct Answer: C
Rationale: When a B-cell undergoes immunoglobulin class switching, the variable region of the heavy chain remains the same but its constant region changes. This process allows the B-cell to produce antibodies with different effector functions while maintaining the same antigen specificity. By changing the constant region of the heavy chain, the B-cell can switch from producing IgM to IgG, IgA, or IgE antibodies. Choices A, B, and D are incorrect because they do not accurately describe the specific changes that occur during immunoglobulin class switching in B-cells.
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A patient’s documentation indicates he has a stage III pressure ulcer on his right hip. What should the nurse expect to find on assessment of the patient’s right hip?
- A. Exposed bone, tendon, or muscle
- B. An abrasion, blister, or shallow crater
- C. Deep crater through subcutaneous tissue to fascia
- D. Persistent redness (or bluish color in darker skin tones)
Correct Answer: C
Rationale: Stage III pressure ulcers penetrate through all layers of the skin but do not expose underlying structures such as bone or muscle.
Select the correct statement during an allergic reaction.
- A. An allergen binds with IgE antibodies.
- B. The mast cells are deactivated.
- C. The body is immunodeficient.
- D. Helper T cells release histamine.
Correct Answer: A
Rationale: Step-by-step rationale:
1. During an allergic reaction, allergens trigger the release of IgE antibodies.
2. The allergen binds with IgE antibodies, leading to the activation of mast cells.
3. Activated mast cells release histamine and other inflammatory mediators.
4. This cascade of events causes allergic symptoms.
Therefore, option A is correct as it accurately describes the initial binding of allergen with IgE antibodies. Option B is incorrect as mast cells are activated, not deactivated. Option C is incorrect as the body is hypersensitive, not immunodeficient. Option D is incorrect as it is mast cells, not Helper T cells, that release histamine.
A client calls the clinic to report exposure to poison ivy and an itchy rash that is not helped with over-the-counter antihistamines. What response by the nurse is most appropriate?
- A. Antihistamines do not help poison ivy.
- B. There are different antihistamines to try.
- C. You should be seen in the clinic right away.
- D. You will need to take some IV steroids.
Correct Answer: C
Rationale: The correct answer is C: "You should be seen in the clinic right away." This response is appropriate because poison ivy rashes can worsen and may require prescription medications like corticosteroids. Seeing a healthcare provider ensures proper diagnosis and treatment.
A: "Antihistamines do not help poison ivy." - Incorrect, as antihistamines may provide some relief for itching but are not the primary treatment for poison ivy rashes.
B: "There are different antihistamines to try." - Incorrect, as trying different antihistamines may not address the underlying issue of poison ivy exposure.
D: "You will need to take some IV steroids." - Incorrect, as IV steroids are typically reserved for severe cases and should be prescribed by a healthcare provider after evaluation.
Which of the following statements is incorrect?
- A. The gut microbiome composition in obese individuals is altered and shows overrepresentation of less beneficial species
- B. Fecal transplants have been used to treat Clostridium difficile infections
- C. Crohn's disease is considered a disease caused by loss of tolerance to the gut microbiota
- D. The bacterial type III secretion system is used by species of the gut microbiota to inject effector proteins into intestinal epithelial cells and invade them, as observed in Crohn's disease
Correct Answer: D
Rationale: The correct answer is D because the statement incorrectly implies that the bacterial type III secretion system is used by gut microbiota to invade intestinal epithelial cells in Crohn's disease. In reality, Crohn's disease is not directly caused by invasion of gut microbiota into intestinal cells; it is a complex autoimmune condition. The gut microbiota dysbiosis is associated with Crohn's disease, but invasion of epithelial cells is not the primary mechanism. Choices A, B, and C are correct: A highlights the altered microbiome in obesity, B discusses the use of fecal transplants for C. difficile infections, and C mentions Crohn's disease related to issues with gut microbiota tolerance.
In a patient with a CD4 count less than 200, the most important nursing assessment would include:
- A. Bowel movements.
- B. Urinary output.
- C. Fever.
- D. Blood pressure.
Correct Answer: C
Rationale: A CD4 count below 200 indicates advanced HIV infection (AIDS), making the patient highly susceptible to opportunistic infections. Fever is a key sign of infection and requires immediate attention. Bowel movements and urinary output are less urgent priorities in this context.