ATI RN
ATI Immune System Quizlet Questions
Question 1 of 5
One principal function of the Class I and Class II major histocompatibility complex S proteins is to
Correct Answer: C
Rationale: The correct answer is C because Class I and Class II MHC proteins present antigens to T-cell receptors for immune response activation. Class I MHC presents endogenous antigens to CD8+ T cells, while Class II MHC presents exogenous antigens to CD4+ T cells. Choice A is incorrect because MHC proteins do not transduce signals. Choice B is incorrect because MHC proteins do not mediate immunoglobulin class switching. Choice D is incorrect because MHC proteins do not directly stimulate interleukin production.
Question 2 of 5
When the clinic nurse starts to take the "air cast" off the grade 2 sprain, the patient asks why it is being removed since he still has pain. Which explanation is best?
Correct Answer: C
Rationale: The correct answer is C because long-term immobilization can indeed cause permanent disability in the case of a grade 2 sprain. Prolonged immobilization can lead to muscle atrophy, joint stiffness, and decreased range of motion, which can result in long-term disability. Choice A is incorrect because adequate circulation is more related to prolonged immobilization, not short-term removal for evaluation. Choice B is incorrect as edema is a short-term concern and not a direct result of long-term immobilization. Choice D is incorrect as there is no indication that a heavier cast will be used.
Question 3 of 5
The nurse is performing an assessment on the patient who is in bilateral Buck traction. Which finding indicates the need to reposition the patient?
Correct Answer: C
Rationale: The correct answer is C because if the patient's feet are against the footboard in Buck traction, it can cause pressure ulcers and compromise circulation. Repositioning the patient is necessary to ensure proper alignment and prevent complications. Incorrect choices: A: The patient's heels not touching the mattress can be due to the traction pulling the legs in a specific position. B: Rewrapping the elastic bandages may be necessary for proper traction maintenance but doesn't indicate immediate need for repositioning. D: The weights hanging free is a normal finding in Buck traction and indicates proper traction application.
Question 4 of 5
The interaction of a TCR with its specific antigen is denoted as "signal 1" of activation and does NOT need the contribution of which of the following components
Correct Answer: C
Rationale: Step-by-step rationale: 1. "Signal 1" activation requires TCR to interact with its specific antigen. 2. TCR consists of α and β chains, which are essential for antigen recognition. 3. MHC molecule is crucial for presenting antigens to TCR for recognition. 4. Choice C (28) is not a component involved in TCR-antigen interaction. 5. Therefore, the correct answer is C as it does not contribute to "signal 1" activation. Summary: A and B are incorrect as TCR α and β chains are necessary for antigen recognition. D is incorrect as MHC molecule is essential for presenting antigens to TCR. C is correct as it is not involved in the TCR-antigen interaction process.
Question 5 of 5
Which of the following statement is incorrect
Correct Answer: B
Rationale: The correct answer is B because migrating dendritic cells do not enter the draining lymph node (LN) via high endothelial venules (HEV); instead, they enter through afferent lymphatic vessels. HEVs are specialized post-capillary venules in LN where lymphocytes enter from the bloodstream. Dendritic cells, carrying antigens from tissues, travel via afferent lymphatic vessels to reach the LN where they present antigens to lymphocytes. Option A is correct as antigens in tissues reach LN via afferent lymphatic vessels. Option C is correct as infection-induced signals can increase blood flow to LN, facilitating lymphocyte migration. Option D is incorrect because the thoracic duct returns lymph back to the bloodstream, not specifically lymphocytes.