Nokea
All of the following are true EXCEPT
- A. An epitope is a small portion of a macromolecule
- B. the variable region domains contain the antigen recognition site
- C. an antigenic determinant is a paratope
- D. The class of an immunoglobulin is determined by its heavy chain
Correct Answer: C
Rationale: The correct answer is C because an antigenic determinant is not a paratope, but an epitope. Epitope is a small portion of a macromolecule that is recognized by antibodies. Variable region domains of antibodies contain the antigen recognition site. The class of an immunoglobulin is indeed determined by its heavy chain. Therefore, C is the only statement that is not true.
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Which antibodies are involved in Type II hypersensitivity?
- A. IgE and IgA
- B. IgG and IgM
- C. IgD and IgG
- D. IgM and IgA
Correct Answer: B
Rationale: The correct answer is B (IgG and IgM) because in Type II hypersensitivity, antibodies target antigens on cell surfaces or tissues. IgG and IgM antibodies are involved in this type of immune response by binding to antigens and triggering cell destruction through complement activation or phagocytosis. IgE and IgA (choice A) are typically associated with Type I and Type III hypersensitivity, respectively. IgD (choice C) is primarily involved in B cell activation, while IgA (choice D) is more commonly associated with mucosal immunity.
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.
What is the role of complement component C3b in immune responses?
- A. Initiates MAC formation
- B. Acts as an opsonin to enhance phagocytosis
- C. Triggers inflammation
- D. Neutralizes cytokines
Correct Answer: B
Rationale: The correct answer is B: C3b acts as an opsonin to enhance phagocytosis. C3b binds to pathogens and enhances their recognition by phagocytic cells, facilitating their engulfment and destruction. This process is crucial for efficient immune responses. A, MAC formation, is initiated by the membrane attack complex, not C3b. C, inflammation, is triggered by various mediators such as histamine and cytokines, not C3b. D, neutralizing cytokines, is not a function of C3b; cytokines are regulatory proteins involved in immune responses.
The nurse is performing an assessment on the patient who is in bilateral Buck traction. Which finding indicates the need to reposition the patient?
- A. The patient's heels are not touching the surface of the mattress.
- B. The elastic bandages need to be revrapped.
- C. The patient's feet are against the footboard.
- D. The weights are hanging free.
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.
The reason for naming the closed circulatory systems
- A. Carries blood in opens vessels
- B. Moves blood through the veins and arteries
- C. Blood stays confined to vessels
- D. Returns blood to the heart
Correct Answer: C
Rationale: The correct answer is C because a closed circulatory system means that blood stays confined to vessels, providing efficient transport and preventing blood loss. Option A is incorrect because a closed system does not have open vessels. Option B is incorrect because veins and arteries are part of both closed and open circulatory systems. Option D is incorrect because returning blood to the heart is a function of both closed and open circulatory systems.