Immunology Qs - Part #2 M.Tawalbeh

Part #2

1. An example of innate immunity is: a. Antibody production by plasma cells. b. Antigen removal by cilia in the respiratory tract. c. Complement activation by antibody bound to the surface of a bacterium. d. Memory response to influenza virus. e. Recognition and killing of virus infected cells by cytotoxic T cells. Answer:b 2. Humoral immunity can be acquired passively by: a. Catching a virus from a friend by shaking hands. b. Receiving a vaccine of influenza virus grown in eggs. c. Receiving serum from someone who recovered from an infection. d. Receiving leukocytes from an immune family member. e. Sharing a soda with someone who has a cold. Answer:c 3. The antibiotic penicillin is small molecules that dose not induce antibody formation. However, penicillin binds to serum proteins and forms a complex that in some people induces antibody formation, resulting in an allergic reaction. Penicillin is therefore: a. An antigen. b. A hapten. c. An immunogen. d. Both a and b e. Both a and c answer:d 4. For specific antigen antigen recognition by T cells: a. Antigen is bound a T‐cell membrane antibody. b. Denaturation of antigen dose not reduces epitope recognition. c. Developing T cells must be exposed to the antigen. d. MHC molecules are not required. e. Soluble antigen is bound directly without processing

answer:a 5. Effector functions of complement complement include all of the following except: a. Attracting phagocytes to the site of infection. b. Facilitating phagocytosis of complement‐coated bacteria. c. Increasing blood vessels permeability to plasma proteins. d. Lysing bacterial cells. e. Presenting antigen to B cells. Answer:e 6. Antigen epitopes recognized by ______________ tend to be  ____________.  ____________. a. B cells; highly accessible sites on the exposed surface of antigen. b. Cytotoxic T cells; highly accessible sites on the exposed surface of the antigen. c. Complement; highly accessible sites on the surface of APC. d. Helper T cells; associated with MHC class I on infected cells. e. Macrophages; associated with MHC class II on APCs.

7. Which statement about antigen epitopes is false? a. An epitope may be shared by two different antigens. b. A protein molecule usually contains multiple epitopes. c. B cells bind only processed antigen epitopes. d. Epitopes may be linear or assembled. assembled. e. Some epitopes are more immunogenic that others answer:c 8. Phagocytosis: Phagocytosis: a. Can be stimulated by antigen binding to complement or antibody. b. Is an antigen‐specific antigen‐specific process. c. Must be preceded by antigen processing. d. Rids the body of virus‐infected virus‐infected cells. e. Only occurs after plasma cells begin secreting antibody answer:a

9. Jenner observed that milkmaids who were infected with cowpox were later immune to smallpox infections. infections. This an example of a(n): a. Acquired immunity of barriers skin cells. b. Active immunization with a non‐releated organism that causes similar symptoms. c. Innate immunity of milkmaids to smallpox. d. Memory response to a cross‐reactive cross‐reactive antigen. e. Passive immunization from contact with cow’s milk antibodies. Answer:d 10. ELISA: a. Detect agglutination of cells by antibodies specific for cell surface antigen. b. Uses isotope‐labeled antibodies to detect extremely small amounts of  antigen. c. Is used to isolate cell populations or proteins (including antibodies). d. Uses enzyme‐linked anti IgG to detect serum antibody to specific antigen. e. None of the above. Answer:d

11. All specific lymphocytes have surface molecules that serve as specific receptors for the antigen for which that lymphocyte is specific. In the case of the B-lymphocy B -lymphocyte, te, this surface receptor has a molecular configuration that is virtually identical to which one of the following? a. A cytokine. b. An MHC molecule. c. The antigen for which that B ‐lymphocyte is specific (known as complementary configuration). d. An antibody molecule. Answer:d 12. B cell maturation occurs in: a. The thymus. b. The bone marrow. c. The lymph nodes.

d. The spleen. e. The peyer’s patches. Answer:b

13. Antibody cross‐reactivity cross ‐reactivity is demonstrated by antibody binding to: a. Cell surface marker. b. A hapten. c. A hapten‐carrier hapten‐carrier complex. d. An antigen that is structurally similar to the immunogen. e. The immunogen. Answer:d 14. Which of the following is an example of passive acquired immunity? a. Antibodies secreted in breast milk. b. Anti‐snake bite serum. c. A tetanus shot. d. Antibodies genertated by catching a cold. e. Antibodies transferred through the placenta. Answer: b 15. A component that facilitates phagocytosis when bound to a microorganism: a. Antigen. b. KDO c. Capsule d. Opsonins e. bactoprenol bactoprenol answer: d 16. immunoglobulin classes may not be distinguished by the type of: a. Light chain they possess. b. Carbohydrate on their light chain. c. Constant regions in their light chain. d. Heavy chains they posses. e. None of the above.

Answer: a 17. The constant regions in heavy chains determine: a. Fc receptor binding. b. Conformation of the binding site to the epitope. c. Affinity of the complement receptors. d. Interaction of the Fab with cytokines. e. None of the above. Answer: a

18. Serum from an AB positive, Rh negative patient agglutinates red blood cells from a patient who is Rh negative. What is likely blood type is the second patient? a. It can’t be determined determined from the information provided. b. Type A c. Type B d. Type O e. Type AB answer: a

19. In the early stage of a primary immune response, dendritic dendritic cells present antigen to helper T cells. In this process, to which protein are antigen fragments bound? a. Membrane IgM & IgD. b. IgG bound to plasma membrane FcRγ receptor. c. IgE bound to plasma membrane FcRε receptor. d. Class I MHC e. Class II MHC answer: e

20. Breast‐fed infants have fewer intestinal infections than do infants fed 20. on cow’s milk, because because of 

protection provided by antibodies in breast milk. Of what isotype are the majority of these protective antibodies? a. IgA b. IgG c. IgM d. IgD e. IgE answer: a

21. doesn't fix complement a) IgG2 b) IgG3 c) IgG4 d) IgG1 answer:c 22. elimination of bacteria by opsonization a) neutralization of bacterial toxin b) recognition of bacteria bound antibodies by Fc receptor on macrophage c) prevention of bacteria adhesion to endothelial cell d) binding antibodies Fc on bacteria e) class 1 MHC antigen answer : b 23.MHC I and MHC II a) Constituvely expressed by most cells in the b) expressed by Macrophage and dentritic cell c) Constituvely associated  – hapten d) Expressed – INF gamma 28) Injecting Complement C killing antigen-Ab in patient lacks C3 Answer: b 24. Which one has J chain? a) IgD, IgA2 b) IgG2, IgE c) IgE, IgM d) IgG3, IgA1 e) IgA1, IgM

answer: e 25. Not found on mature resting T cell a) CD5 b) MHC II c) MHC I d) CD2 e) CD3 answer: b 26. Recognition receptor functions as secreted receptor a) Mannan binding lectin b) CD 14 c) Toll like receptor answer: a 27. Ab destruction by pepsin yields a) (F(ab'))2 fragments

28. Which is wrong concerning epitopes? a) Epitope is always immunogenic 29. Allelic exclusion EXCEPT a) On one B lymphocyte you may find both a and b heavy chains 30. Immunogenic means a) Stimulates the immune system 31. In a non-emergency non-emergency situation, a patient of blood type A requires transfusion of plasma. Person of  which ABO types would be regarded as compatible donors? A. Either A or O. B. Either B or O. C. Either B or AB. D. Either A or AB. E. Either AB or O. Answer:a

32. In an immune response immunoglobulin genes undergo somatic mutation. What is the goal of this somatic mutation? A. Increase in antibody affinity. B. Antibody class switching (for example, from IgM to IgG). C. Allow a single b cell to produce antibody of several isotypes. D. Change in type of light chain produced (from kappa to lambda or the reverse). E. Production of anti-class IIMHC antibodies. Answer: a 33. The blood bank lab report indicates that a patient is Rh-positive. Which interpretation interpretation of these statements is most accurate? A. The patient’s plasma contains IgG antibodies to the Rh0 (D) antigen. B. The patient’s plasma contains IgM antibodies to the Rh0 (D) antigen. C. The patient’s erythrocytes carry the Rh0 (D) antigen. D. The patient’s erythrocytes lack the Rh0 (D) antigen Answer: c

34. In the laboratory a serological reagent, prepared from serum of a single donor, was found to bind a multivalent antigen with high affinity, cross-link antigen to form precipitate, and, when bound to antigen, activate complement. Which phrase would best describe the structure of this reagent? a. Fab fragment of IgG. b. Fc fragment of IgG. c. (Fab’) 2 fragment of IgG. d. Intact IgG. Answer: d 35. What process was most responsible for the increase in antibody affinity and avidity? a. Random splicing of V/D/J segments of heavy-chain genes and v/j segments of light chain. b. Excision of constant-region exons from DNA, so that assembled heavychain variable-region exons becomes adjacent to constant-region exons of different DNA sequence.

c. Random addition of nucleotides at V/D and D/J splice junctions of heavychain genes and V/J splice junction of light-chain genes. d. Mutations of variable domain exons of heavy and light chains, followed by selection for the ability to bind epitopes. Answer: d

36. J-chains are not associated with: a. IgG.  b. Polymeric immunoglobulin immunoglobulinss (more than two Fab’s). c. Secretory IgA. d. IgM. e. None of the above. Answer: a 37. Actively acquired immunity is not the result of: a. Transfer of bone marrow from one individual to another. b. Immunization with a vaccine. c. Exposure to an individual who has an infectious disease. d. A physician administering a gamma globulin shot to someone who has had a needle stick  (immunoglobulins). e. A & D answer:d

38. IgD antibody functions as: a. Antigen receptors on immature t cell. b. An ADCC receptors of NK cells. c. A hormone receptor on NK cells. d. A trigger of the complement cascade. e. None of the above. Answer: e 39. Antibody affinity is primarily determined by the amino acid sequence s equence in: a. The constant regions of the immunoglobulin molecule. b. The variable regions of the immunoglobulin molecule. molecule. c. The Fc of the immunoglobulin molecule.

d. The j-chain. e. None of the above. Answer:b

40. The antigen presenting cell: a. May be a dendritic cell in the skin. b. Is not a T cell. c. Produces cytokines which influence the adaptive response. d. Processes antigen prior to presentation to the T cell. e. All of the above. Answer: e 41. NK cells recognize tumor cells using: a. Pattern recognition receptors. b. Antibody-like receptors. c. Complement receptors. d. A homing mechanism. e. None of the above. Answer:a

42. After isotype switching, IgM and IgG can be produced in which variable domains of heavy and light chains, and constant domains of light chains, are identical, but constant domains of  heavy chains differ. Which statement below about such pairs of antibodies is most likely to be true? a. IgM will have lower affinity than IgG. b. IgM will have higher affinity than IgG. c. IgM will be capable of activating complement, but IgG will not. d. IgM molecules will be smaller than IgG molecules. e. IgM and IgG will molecules will bind different epitopes. Answer:c 43. Many isolates of the bacterium Neisseria meningitides can produce mucosal infections but cannot survive in the bloodstream. Cells of such bacteria are killed by contact with cell-free plasma or serum, even from persons who have never previously been exposed to Neisseria. Which mechanism is most likely to be responsible for the

killing? a. Activation of complement by the alternate pathway. b. Activation of complement by the classical pathway. c. Binding of IgG. d. Binding of IgM. e. Binding of IgA. Answer:a

44. Once H chain genes have been productively rearranged rearranged and expressed on the pre-B cell membrane, the next event to occur in the cell is: a. Death of cells binding self antigen. b. Expression of membrane IgD. c. Expression of membrane IgM. d. Proliferation of the pre-b cells. e. Somatic recombination of light chain genes. Answer: e

45. Pepsin digestion of an IgG antibody against tetanus toxoid will: a. Result in loss of the ability to form a lattice with the toxoid. b. Produce two Fab molecules & one Fc fragment c. Produce a (Fab)2 molecule & loss of the ability of the Fc fragment to bind to macrophages. d. Loss of the L chain e. Loss of the C1 heavy chain constant domain answer: c 46. The most important Ig protecting a 1-month-old baby is: a. IgM b. IgG c. IgA d. IgE e. IgD answer: b 47. An advantage of adaptive recognition over innate recognition is that it: a. Faster b. Cannot result in the recognition of the body's own tissues

c. Triggers an inflammatory response d. Targets specific strains of potential pathogens e. Requires less energy to produce the defensive response answer: d

48. During heavy chain splicing, N-nucleotides addition occurs in: a. The junction between the J region & the constant region. b. The junction between V & D & between D & J region. c. the nucleotides between the exons coding for the membrane-spanning region of the constant chain and the rest of the chain: d. A & B above e. A, B & C

49. Early induced immune responses are a re like adaptive immunity in that they: a. Are antigen specific. b. Demonstrate immune memory. memory. c. Involve macrophages & complement. complement. d. Involve T & B lymphocytes. e. Use presynthesized proteins that can be released quickly upon cell activation. Answer:e 50. Severe combined immunodficiency disease is most likely to exhibit the characteristic (s): a. A genetic defect in the NADPH oxidase system b. A loss in the enzyme adenosine deaminase c. A triad of thrombocytopenia, eczema, eczema, & recurrent infections. d. An absence of T cells, hypocalcemia, & tetany. e. Requires the chemokines CCR-5 fro the disease to progress. f. A defect in the transition from pre-B cells to B cels. g. A selective loss in IgA levels. 51. Which of the following statements statements about a secondary (memory) antibody response is FALSE? a. The secondary response comes from memory B cells. b. The secondary response is faster. c. The secondary response is primary IgM

d. The secondary response produces more immunoglobulins immunoglobulins than the primary response. Answer:c

52. A 20-year-old college student working part-time in a pediatric AIDS clinic develops a viral exanthem with a rash. Her blood is drawn & tested for specific antibodies to varicella-zoster (chickenpox). Anti-varicella immunoglobulin immunoglobulin belonging to which of the following antibody classes would indicate that she is immune to chickenpox? a. IgA b. IgD c. IgE d. IgG e. IgM answer:d

53. An IgG2 molecule is composed of which of the following? a. One alpha, one gamma2, & two kappa chains b. One gamma1 chain & two kappa chains c. Two gamma1 chains & one kappa & one lambda chain d. Two gamma 1 chains & two kappa chains e. Two gamma 2 chains & two kappa chains answer:e 54. The small amounts of immune complexes which form in healthy individuals are normally removed in a process involving Fc receptors expressed by: a. Macrophages. b. PMNs c. B cells d. RBCs e. Mast cells 55. The antigen-specific receptors of B lymphocytes contain only a single: a. Polypeptide chain b. Hypervariable region

c. Site for antigen binding d. Constant domain e. None of the above answer: e 56. Which of the following is true? a. Antibodies are composed of 4 identical polypeptide chains. b. Hypervariable regions are primarily found on the Fc portion of the antibody protein. c. T cell receptor & membrane bound immunoglobulins immunoglobulins have identical structures. d. The antigen binding site is found on the Fab region of the immunoglobulin immunoglobulin molecule. e. The Fc portion of the T cell receptor confers antigen specificity. Answer:d

57. The detection of high & sustained levels of a monoclonal antibody in the serum of a patient most often suggests a malignancy involving: a. Bone marrow derived lymphocytes (myeloma) b. Placental trophoblast cells (choriocarcinoma) c. Thymus derived lymphocytes (leukemia) d. Stromal cells of the lung (mesothelioma) e. Liver hepatocytes (hepatoma) (hepatoma) answer: a 58. Superantigens are: a. Bacterial polysaccharides. b. Able to activate all T cells. c. Antigens that do not require processing & presentation for T cell activation. d. Able to induce B cell differentiation without T cell help e. All of the above. Answer:c