ATI RN
Lymphatic and Immune System Test Questions Questions
Question 1 of 5
What are TCRs?
Correct Answer: B
Rationale: TCRs (T-cell receptors) are on T cells ; B cells have BCRs, not TCRs.
Question 2 of 5
Which of the following molecules is not generally produced by T cells and macrophages?
Correct Answer: D
Rationale: Tissue thromboplastin is a clotting factor, not from T cells/macrophages; growth factors , cytokines , and CSFs are immune-related.
Question 3 of 5
Secondary (or peripheral) lymphoid organs are sites for initiation of adaptive immune responses. Given the rarity of lymphocytes specific for any given antigen and the vast amount of body tissue that must be protected, the system of secondary lymphoid tissues is efficient because:
Correct Answer: A
Rationale: Secondary lymphoid organs concentrate antigens for rare lymphocytes; proliferation follows, trapping or innate clearance are less primary.
Question 4 of 5
As a family, TLRs can recognize PAMPs associated with a broad array of different pathogens, including bacteria, viruses, and fungi. Patients with a specific susceptibility to herpesvirus infections have a defect in their ability to respond to viral nucleic acids using TLR-3, TLR-7, or TLR-9, even though these proteins are expressed in the patients' cells. Analysis of the TLRs in macrophages and dendritic cells from these patients would likely show which of the arrangements in Figure Q3.11?
Correct Answer: A
Rationale: Assuming Q3.11 shows TLR defects, a signaling defect explains susceptibility despite expression; exact arrangement inferred.
Question 5 of 5
In spite of their low affinity for binding to their antigen, IgM antibodies can be quite effective at promoting the elimination of extracellular bacterial infections. This is due to:
Correct Answer: B
Rationale: IgM pentamers bind multivalently , enhancing efficacy; not epithelial , concentration , or timing alone.