ATI RN
Immune System NCLEX Questions Questions
Question 1 of 5
Which co-stimulatory molecule is used by APCs to activate T cells?
Correct Answer: A
Rationale: APCs use B7 to bind CD28 on T cells for co-stimulation ; CD4/CD8 (B, C) are T-cell co-receptors, CD40 is for B cells.
Question 2 of 5
Which of these is not a function of lymph nodes?
Correct Answer: C
Rationale: Lymph nodes house and produce lymphocytes, filter lymph , but red blood cell production occurs in bone marrow, not lymph nodes.
Question 3 of 5
Some Pattern Recognition Receptors (PRRs) recognize nucleic acids, like RNA or DNA. Since our own cells contain human RNA and DNA, the activation of innate immune pathways by these PRRs must rely on additional criteria to discriminate self from nonself. Additional criteria include everything EXCEPT:
Correct Answer: B
Rationale: PRRs distinguish self via RNA location , DNA methylation , and viral RNA structures ; adenosine presence isn't a key discriminator.
Question 4 of 5
Patients with recurrent infections of Neisseria meningitidis, an extracellular bacterial pathogen that causes meningitis, were found to have defects in complement activation on the bacterial surface, a process that for this bacterium is dominated by alternative complement activation leading to C3b deposition on the pathogen surface. Based on these data, the identity of the green neutrophil mediator in Figure Q2.19 is likely to be:
Correct Answer: D
Rationale: C3b is deposited on Neisseria via alternative pathway, aiding neutrophil phagocytosis; Factor B and properdin assist, but C3b is key.
Question 5 of 5
The exon encoding the V region of an immunoglobulin protein is generated by a process of somatic recombination. This recombination event brings V gene and J gene segments together:
Correct Answer: B
Rationale: V-J recombination maximizes CDR3 diversity ; not all cells , not splicing , or precise .