University of Central Florida | PCB 3233 Practice Exam 3 Final (ANSWERS)

Practice Exam 3 Multiple Choice Identify the choice that best completes the statement or answers the question. ____ 1. The -chain locus is positioned within the -chain locus, and is consequently deleted and inactivated during rearrangement of the gene segments. a. True b. False ____ 2. Gene rearrangements of the light chain include all of the following, except: a. At least four possible attempts for a successful rearrangement. b. Rearrangement of the  genes first, and then the  genes. c. If no successful rearrangements are made, apoptosis will result. d. Rearrangement of the  genes first, and then the  genes. ____ 3. T-cell receptors will typically bind antigen using multipoint attachment, which is achieved using two opposing human cell surfaces. a. True b. False ____ 4. Which of the following cell types does NOT express MHC class I? a. Erythrocytes d. Dendritic cells b. Hepatocytes e. Macrophages c. Lymphocytes ____ 5. T-cell receptor diversity is established by: a. somatic hypermutation in the secondary lymphoid tissues b. somatic recombination in the thymus c. somatic hypermutation in the thymus d. somatic recombination in the secondary lymphoid tissues ____ 6. Although T cells differ from B cells in that they require MHC molecules for antigen processing, both T cells and B cells will always bind soluble antigens. a. True b. False ____ 7. Which of the following components are included in the CD3 complex? a. CD3 d. Ig and Ig b. CD3 e. All of the above c. CD3 ____ 8. During the maturation of both B cells and T cells, which of the following enzymes would you expect to be working? a. RAG-1 & RAG-2 d. A & B b. AID e. A & C c. TdT This study source was downloaded by from CourseH on :19:04 GMT -05:00 a. BCL-2 d. CD19 b. CD5 e. Btk c. MYC ____ 10. What population of T cell is identified to be the one found in the greatest amount within our bodies? a.  T cells d.  T cells b.  T cells e. None of the above c.  T cells ____ 11. B cells that bind to self-antigens in the bone marrow can lead to: a. anergy d. A & B b. receptor editing e. A, B & C c. apoptosis ____ 12. B-1 cells: a. are expressed before B-2 cells d. A & B b. produce memory cells e. A & C c. produce Abs of limited diversity and low affinity ____ 13. When comparing the structure of MHC class I to that of MHC class II, you would expect to find the -microglobulin domain associated with MHC class II molecules. a. True b. False ____ 14. Which of the following statements is true about the degradation of extracellular proteins? a. The peptides produced will be delivered to CD8 T cells. b. The peptides produced will be bound to MHC class I molecules. c. The peptides produced will be found in a phagolysosome. d. A & C e. A, B & C ____ 15. During B-cell maturation, the bone marrow stromal cells perform which of the following functions? a. signal to B cells d. A & C b. secrete IL-7 e. A, B & C c. provide a specialized microenvironment ____ 16. Regarding our discussion in class about Burkitt’s lymphoma, which of the following chromosomes are directly affected by a rearrangement? a. 7 & 14 c. 2 & 22 b. 8 & 22 d. 8 & 14 This study source was downloaded by from CourseH on :19:04 GMT -05:00 molecules? a. The alpha & beta chains of MHC class II assemble with the invariant chain. b. Li, a protein, prohibits peptides from binding to MHC class II within the ER. c. In a proteasome, the degradation of intracellular antigen will produce short peptides (8-10 amino acids) to be loaded on the MHC II. d. A & B e. A, B & C ____ 18. Once the light chain has finished rearrangement, the Ig and Ig genes are expected to be turned off (no longer expressed). a. True b. False ____ 19. Antigens that are taken up from the extracellular space will typically be degraded by: a. a proteasome d. an endosome b. TAP-1 & TAP-2 e. A & B c. an immunoproteasome ____ 20. Rearrangement (somatic recombination) of the light chain of the B-cell receptor includes: a. RAG complex activity d. A & C b. MHC restriction e. B & C c. The V and J gene segments ____ 21. An immature B cell is expected to have: a. IgM and Ig & Ig on its surface. b. IgM heavy chain with the surrogate light chain. c. IgD heavy chain with the surrogate light chain. d. IgM, IgA, and Ig & Ig on its surface. e. None of the above. ____ 22. The first checkpoint in B-cell maturation: a. involves a pre-BCR. b. checks for functional rearrangement of the L-chain variable domain gene segments. c. utilizes -microglobulin and VpreB attached to the heavy chain. d. A & B e. A, B & C ____ 23. From our discussion in class about the assembly and loading of peptide with MHC class I, you would expect this overall process to be occurring within the _______ of the cell. a. Cytosol d. Cytoplasm b. Nucleus e. Golgi apparatus c. Endoplasmic reticulum This study source was downloaded by from CourseH on :19:04 GMT -05:00 a. True b. False ____ 25. Human MHC class __ isotypes, such as HLA-A, HLA-B, and HLA-C, will present peptide to ___ T cells. a. I ; CD4 c. II ; CD4 b. I ; CD8 d. II ; CD8 This study source was downloaded by from CourseH on :19:04 GMT -05:00 Answer Section MULTIPLE CHOICE 1. ANS: B PTS: 1 2. ANS: D PTS: 1 3. ANS: A PTS: 1 4. ANS: A PTS: 1 5. ANS: B PTS: 1 6. ANS: B PTS: 1 7. ANS: B PTS: 1 8. ANS: E PTS: 1 9. ANS: C PTS: 1 10. ANS: C PTS: 1 11. ANS: E PTS: 1 12. ANS: E PTS: 1 13. ANS: B PTS: 1 14. ANS: C PTS: 1 15. ANS: E PTS: 1 16. ANS: D PTS: 1 17. ANS: D PTS: 1 18. ANS: B PTS: 1 19. ANS: D PTS: 1 20. ANS: D PTS: 1 21. ANS: A PTS: 1 22. ANS: A PTS: 1 23. ANS: C PTS: 1 24. ANS: A PTS: 1 25. ANS: B PTS: 1 This study source was downloaded by from CourseH on :19:04 GMT -05:00 Powered by TCPDF ()