Exam 1

Answer Key For Odd Numbered Exams: 1. A 2. D 3. C 4. D 5. E 6. B 7. D 8. D 9. D 10. A 11. D 12. C 13. B 14. A 15. C 16. C 17. C 18. E 19. E 20. A 21. B 22. B 23. A 24. B 25. B 26. A 27. B 28. B 29. A 30. B 31. B 32. A 33. A 34. A 35. B 36. A 37. A 38. B 39. B 40. A 41. A 42. B 43. B 44. A 45. A 46. B Spring 2009 Exam I Questions 1-20: Select one answer for each question (1 point/question): 1. Which of the following events does NOT occur during an inflammatory response? a. red blood cells move out of the blood vessels into the wounded tissue b. endothelial cells in the infected area shrink c. blood moves more slowly through the blood vessels in the infected area d. proteins “leak” ouf o the blood vessels in the infected area e. all of the above occur during an inflammatory response 2. During pregnancy, what antibody is transported from the mother’s blood vessels into the fetal blood vessels in the placenta? a. the same antibody that forms a pentamer when secreted b. the same antibody that forms dimers when secreted c. the same antibody that causes allergies d. the same antibody that helps macrophages phagocytose antigens e. the same antibody that is constantly secreted into mucus 3. If a patient lacked M cells, what would you expect to see in their body? a. a decrease in follicles in the respiratory tract b. an increase in the number of neutrophils c. a decrease in the number of Peyer’s Patches d. an increase in the number of Langerhans cells e. a decrease in the number of Langerhans cells 4. What is the difference between toll like receptor 4 (TLR4) and T cell receptors (TCR)? a. only one (either TLR4 or TCR) binds directly to an antigen b. only one (either TLR4 or TCR) binds to an opsin c. only one (either TLR4 or TCR) is located on the plasma membrane d. only one (either TLR4 or TCR) is produced by DNA rearrangement e. more than one of the above correctly describes a difference between TLR4 and TCR 5. What is the difference between naïve B cells and activated B cells? a. only one of the B cells (either naïve or newly activated) have IgM b. only one of the B cells (either naive or newly activated) have IgD c. only one of the B cells (either naïve or newly activated) are proliferating d. only one of the B cells (either naïve or newly activated) are found in germinal centers e. more than one of the above correctly describes a difference between naïve and newly activated B cells 6. What is the purpose of the enzymes in neutrophil granules? a. to kill cells infected with a virus b. to break apart extracellular matrix c. to activate the complement proteins d. to increase production of cytokines e. to destroy endothelial cells 7. Why is the thoracic duct so important? a. it is used by T cells to leave the thymus b. it is used by blood cells to leave the bone marrow c. it is used by B and T cells to enter the lymph nodes d. it allows lymphocytes and lymph to enter the blood circulation e. it allows antigens to enter the spleen 8. What happens to a patient during septic shock? a. bacteria invade the liver and destroy the cells in the liver b. TNF binds to liver cells and recruits complement proteins to destroy the liver cells c. autoreactive antibodies bind to liver cells and cause the liver cells to be destroyed d. TNF binds to liver cells and the liver cells stop breaking apart glycogen to release glucose e. a patient develops a fever that kills the liver cells 9. If the epitopes on an antigen are far apart from each other, which of the following structures is most likely to bind two epitopes? a. an Fab fragment with a J chain b. an Fab fragment with a hinge region c. an F(ab’)2 fragment with a J chain d. an F(ab’)2 fragment with a hinge region e. an Fc fragment with two hinge regions 10. What quality is shared between passive immunity and active immunity (how are they similar)? a. active immunity and passive immunity both involve antibodies b. active immunity and passive immunity both involve the production of memory cells c. active immunity and passive immunity are both activated by vaccines d. active immunity and passive immunity are provided by a mother during pregnancy and used to protect the developing fetus e. more than one of the above qualities are shared between passive and active immunity 11. In order for a myeloid progenitor cell to differentiate into a macrophage, what cytokine needs to be delivered to the myeloid progenitor? a. IL-2 b. IL-7 c. TNF d. GM-CSF e. erythropoietin 12. What is the difference between the innate and adaptive immune response? a. the innate immune response only involves proteins and the adaptive immune response only involves cells b. the innate immune response uses cytokines to fight an infection and the adaptive immune response uses phagocytic cells to fight an infection c. adaptive immune cells undergo multiple rounds of cell division after they are stimulated by antigens and innate immune cells do not d. the innate immune response is more diverse and able to protect against more antigens than the adaptive immune response e. the innate immune cells develop into memory cells and the adaptive immune cells die too quickly to produce memory cells 13. What antibody is found on the surface of immature B cells? a. the same antibody that is not secreted b. the same antibody that forms a pentamer when it is secreted c. the same antibody that is found primarily in the mucus d. the same antibody that forms a dimer when it is secreted e. the same antibody that helps macrophages phagocytose antigens 14. What is the role of helper T cells? a. helper T cells secrete cytokines that stimulate other immune cells b. helper T cells secrete cytokines that bind to infected cells and stimulate apoptosis of the infected cell c. helper T cells phagocytose viruses and bacteria d. helper T cells secrete antibodies e. all of the above 15. If someone has an infection in their big toe, where would the draining lymph node most likely be located? a. under the arm b. near the pelvic region c. behind the knee d. behind the jaw e. behind the lungs 16. What steps occur when a naïve T cell is activated? a. the T cell immediately differentiates into an effector cell, then the effector cell proliferates b. the T cell immediately differentiates into a memory cell, then the memory cell proliferates c. the T cell proliferates then differentiates into an effector cell or memory cell d. the T cell proliferates and produces enough daughter cells to stop the infection within 3-4 days e. a and b 17. What is the difference between macrophages and neutrophils? a. macrophages continuously circulate in the blood, most neutrophils are found within tissues b. macrophages use Toll Like Receptors to bind to antigens, neutrophils only use opsin receptors to bind to antigens c. macrophages secrete growth factors to help with wound healing, neutrophils do not d. macrophages circulate in the lymph, neutrophils circulate in the blood e. macrophages shortly after phagocytosis, neutrophils survive for 2-3 weeks after phagocytosis 18. When T cells migrate into the spleen, where do they go? a. the paracortex b. the cortex c. the high endothelial venules d. the medulla e. the P.A.L.S. 19. If you were a scientist who discovered a new TLR that binds to viral RNA, where would you expect the TLR to be located and why? a. in the plasma membrane in order to activate more signaling pathways b. in the plasma membrane where the TLR will most likely engage its ligand c. in the nuclear membrane because that is the first place viral RNA will migrate to after phagocytosis d. in the endosomal membrane in order to activate phagocytosis e. in the endosomal membrane where the TLR will most likely be exposed to its ligand 20. Why are the high endothelial venules (HEVs) so important? a. without the HEVs, lymphocytes can not enter the lymph nodes b. without the HEVs, lymphocytes can not enter infected tissues c. without the HEVs, lymphocytes can not leave the bone marrow d. without the HEVs, lymphocytes can not leave the thymus e. without the HEVs, lymphocytes can not enter the spleen Questions 21-45: True/False. Choose one answer for each question. (1 point/question) 21. Edward Jenner developed the first vaccine in the world that was able to protect against smallpox. a. True b. False 22. Patients with chronic infections have an excess or high level of large immune complexes. a. True b. False 23. Mice that lack IL-7 also lack B cells and T cells, but have normal numbers of neutrophils. a. True b. False 24. Dimeric IgA usually has a similar avidity for bivalent antigens as dimeric IgG. a. True b. False 25. Activated T cells and dendritic cells express the chemokine receptor CCR7. a. True b. False 26. IgG, C-reactive protein, and mannose binding lectin are all opsins. a. True b. False 27. Hassal’s Corpuscles are found in the same organ as marginal zone B cells. a. True b. False 28. B and T cells use E-selectin to bind to high endothelial venules. a. True b. False 29. Complement proteins and natural killer cells can be activated by the same isotype of antibody. a. True b. False 30. Antigens enter the spleen and lymph node using different mechanisms, but activated B and T cells use the same structures to leave both the spleen and the lymph node. a. True b. False 31. Germinal centers contain activated B cells and are found in primary follicles. a. True b. False 32. During isotype switching, B cells change their Fc regions and during affinity maturation, B cells change their CDRs. a. True b. False 33. Without integrins, neutrophils can roll along blood vessels, but they can not extravasate. a. True b. False 34. T cells mature as they move from the cortex to the medulla of the thymus. a. True b. False 35. Pre-B cells are identified by the (delta) heavy chain located in their cytoplasm. a. True b. False 36. The antibody that forms dimers when secreted is also found in breast milk. a. True b. False 37. IL-1 and IL-10 have opposite affects on the immune response. a. True b. False 38. To discriminate between macrophages and neutrophils, hydrogen peroxide levels could be measured since hydrogen peroxide is not produced by both cell types. a. True b. False 39. Bone marrow stromal cells provide growth factors that help B cells differentiate from pre-B eventually into mature B cells and growth factors that also help developing T cells differentiate from a pre-T eventually into a mature T cell. a. True b. False 40. When free antigens enter lymph nodes they are usually captured first by macrophages. a. True b. False 41. Self antigens are normally tolergens and bacterial proteins are usually immunogens. a. True b. False 42. Each light chain contains two immunoglobulin domains and each of those immunoglobulin domains contains beta-pleated sheets and three CDRs. a. True b. False 43. The antibody isotype that causes allerrgies forms a trimer when it is secreted, allowing the antibody to bind tightly to allergens. a. True b. False 44. People who lack regulatory T cells are more likely to get autoimmune diseases. a. True b. False 45. In the lymph node, the highest concentration of CXCL13 is found in the cortex. a. True b. False Extra Credit (I point) 46. We discussed a new vaccine being developed to treat Alzheimer’s Disease. How does the new vaccine work? a. by using Langerhans cells to induce an inflammatory response b. by using Langerhans cells to induce a non-inflammatory response c. by using Microglial cells to induce an inflammatory response d. by using Microglial cells to induce a non-inflammatory response