ATI RN
Pediatric Immunization Practice Questions Questions
Question 1 of 5
Regarding the structure of the T-cell receptor, which of the following is NOT an invariant CD3 protein chain?
Correct Answer: A
Rationale: The TCR includes CD3 chains (γ, δ, ε) and theζ chain, butζ is not traditionally classified as a CD3 chain; it's part of the associatedζ-ζ homodimer.
Question 2 of 5
The mutation on the X chromosome responsible for X-SCID is in the gene for a subunit of several cytokine receptors. Which of the following is true for boys affected with X-SCID at birth?
Correct Answer: A
Rationale: X-SCID (IL-2Rγ mutation) impairs T, B, and NK cell function.
Question 3 of 5
Paracortex
Correct Answer: B
Rationale: The paracortex is rich in T cells, especially CD4+.
Question 4 of 5
Lymphocyte passage (diapedesis or transmigration) occurs at the between adjacent endothelial cells then into the tissues.
Correct Answer: C
Rationale: Diapedesis occurs at adherens junctions between endothelial cells.
Question 5 of 5
Allelic exclusion creates monospecific B-cell receptors (BCRs). The result is these cells each secrete:
Correct Answer: D
Rationale: Allelic exclusion ensures each B cell produces antibodies with one specificity.