1. What is immunogenetics?
A) The study of immune responses in animals
B) The study of genetic factors influencing immune system function
C) The study of animal behavior related to immunity
D) The study of environmental factors affecting immune health
Answer: B
2. Which of the following is a major histocompatibility complex (MHC) molecule involved in immune recognition?
A) CD4
B) IgG
C) MHC-I
D) Cytokines
Answer: C
3. What is the role of MHC molecules in immune responses?
A) Producing antibodies
B) Recognizing self from non-self antigens
C) Activating complement proteins
D) Killing infected cells
Answer: B
4. Which type of immune cells are involved in the adaptive immune response?
A) Neutrophils
B) Macrophages
C) T cells and B cells
D) Natural killer cells
Answer: C
5. What is the function of T cells in the immune system?
A) Producing antibodies
B) Phagocytosis of pathogens
C) Directly killing infected cells
D) Secreting cytokines
Answer: C
6. Which of the following is a characteristic of the innate immune system?
A) Specificity for antigens
B) Memory response to pathogens
C) Rapid response to pathogens
D) Production of antibodies
Answer: C
7. What is the role of antibodies in immune responses?
A) Phagocytosis of pathogens
B) Recognizing and neutralizing antigens
C) Producing cytokines
D) Initiating complement activation
Answer: B
8. What is the primary function of the complement system in immunity?
A) Producing antibodies
B) Directly killing pathogens
C) Activating T cells
D) Regulating cytokine production
Answer: B
9. Which of the following is an example of an antigen-presenting cell (APC)?
A) T cell
B) B cell
C) Macrophage
D) Natural killer cell
Answer: C
10. What is the significance of Toll-like receptors (TLRs) in immune responses?
A) They are involved in antigen recognition by T cells
B) They activate the complement system
C) They recognize pathogen-associated molecular patterns (PAMPs)
D) They regulate cytokine production
Answer: C
11. How do B cells contribute to adaptive immunity?
A) By directly killing infected cells
B) By producing antibodies that recognize specific antigens
C) By activating T cells
D) By secreting cytokines
Answer: B
12. What is the function of cytokines in immune responses?
A) Producing antibodies
B) Killing infected cells
C) Regulating immune cell activity and communication
D) Phagocytosis of pathogens
Answer: C
13. Which of the following is a primary immunoglobulin (antibody) class involved in immune responses?
A) IgA
B) IgD
C) IgM
D) IgE
Answer: C
14. What is the role of natural killer (NK) cells in the immune system?
A) Producing antibodies
B) Recognizing and killing infected cells
C) Activating complement proteins
D) Phagocytosis of pathogens
Answer: B
15. How does the immune system distinguish self from non-self antigens?
A) Through the production of cytokines
B) Through the action of natural killer cells
C) Through MHC molecules presenting antigens to T cells
D) Through the activation of complement proteins
Answer: C
16. What is the function of memory cells in the adaptive immune response?
A) Phagocytosis of pathogens
B) Recognizing and neutralizing antigens upon subsequent exposure
C) Initiating complement activation
D) Producing antibodies
Answer: B
17. What is the significance of the major histocompatibility complex (MHC) in immune compatibility?
A) It prevents autoimmune diseases
B) It regulates cytokine production
C) It ensures compatibility of tissues and organs for transplantation
D) It promotes phagocytosis of pathogens
Answer: C
18. How does the immune system respond to viral infections?
A) By producing antibodies
B) By activating T cells to kill infected cells
C) By secreting cytokines
D) All of the above
Answer: D
19. What is the function of dendritic cells in immune responses?
A) Producing antibodies
B) Activating T cells by presenting antigens
C) Initiating complement activation
D) Phagocytosis of pathogens
Answer: B
20. Which of the following is a primary function of the thymus gland in the immune system?
A) Producing antibodies
B) Maturation and selection of T cells
C) Activation of complement proteins
D) Regulation of cytokine production
Answer: B
21. How do T cells recognize antigens?
A) Through direct phagocytosis
B) Through interaction with MHC molecules presenting antigens
C) Through complement activation
D) Through production of antibodies
Answer: B
22. What is the role of antigen presentation in immune responses?
A) It activates B cells to produce antibodies
B) It activates natural killer cells
C) It activates T cells by presenting antigens to them
D) It initiates complement activation
Answer: C
23. Which of the following is an example of an autoimmune disease?
A) Rheumatoid arthritis
B) Influenza
C) Chickenpox
D) Tuberculosis
Answer: A
24. What is the significance of the immune tolerance mechanism?
A) It prevents the development of allergies
B) It prevents the immune system from attacking self-cells
C) It activates complement proteins
D) It promotes antibody production
Answer: B
25. How does the immune system respond to bacterial infections?
A) By producing antibodies
B) By activating T cells to kill infected cells
C) By secreting cytokines
D) All of the above
Answer: D
26. What is the role of immunoglobulin E (IgE) in allergic reactions?
A) It promotes immune tolerance
B) It activates natural killer cells
C) It triggers the release of histamine from mast cells
D) It regulates cytokine production
Answer: C
27. What is the function of the spleen in the immune system?
A) Producing antibodies
B) Maturation of T cells
C) Phagocytosis of pathogens
D) Filtering blood and removing old red blood cells
Answer: D
28. How does the immune system respond to parasitic infections?
A) By producing antibodies
B) By activating T cells to kill infected cells
C) By secreting cytokines
D) All of the above
Answer: D
29. What is the role of T helper cells (CD4+ cells) in immune responses?
A) Directly killing infected cells
B) Activating B cells to produce antibodies
C) Initiating complement activation
D) Phagocytosis of pathogens
Answer: B
30. How do T regulatory cells (Tregs) contribute to immune regulation?
A) By promoting inflammation
B) By inhibiting immune responses and maintaining tolerance
C) By activating B cells
D) By promoting antibody production
Answer: B
31. What is the function of natural antibodies in the immune system?
A) Recognizing and neutralizing specific pathogens
B) Promoting autoimmune responses
C) Activating complement proteins
D) Initiating phagocytosis
Answer: A
32. Which of the following is an example of an immunodeficiency disorder?
A) Rheumatoid arthritis
B) Asthma
C) HIV/AIDS
D) Influenza
Answer: C
33. What is the role of cytokines in cell signaling during immune responses?
A) Activating B cells
B) Suppressing T cell activity
C) Regulating immune cell proliferation and differentiation
D) Initiating complement activation
Answer: C
34. What is the function of the bone marrow in the immune system?
A) Producing T cells
B) Producing red blood cells
C) Maturation of B cells
D) Activating natural killer cells
Answer: C
35. How do antibodies facilitate the process of opsonization?
A) By directly killing pathogens
B) By promoting phagocytosis of pathogens by immune cells
C) By activating complement proteins
D) By inducing apoptosis in infected cells
Answer: B
36. What is the role of MHC-II molecules in immune responses?
A) Presenting endogenous antigens to cytotoxic T cells
B) Presenting exogenous antigens to helper T cells
C) Recognizing self from non-self antigens
D) Activating natural killer cells
Answer: B
37. Which of the following is an example of an autoimmune disorder affecting the nervous system?
A) Rheumatoid arthritis
B) Multiple sclerosis
C) Type 1 diabetes
D) Lupus
Answer: B
38. What is the function of memory B cells in the adaptive immune response?
A) Phagocytosis of pathogens
B) Initiating complement activation
C) Producing antibodies upon subsequent exposure to antigens
D) Activating T cells
Answer: C
39. How do dendritic cells contribute to immune responses in lymph nodes?
A) By producing antibodies
B) By presenting antigens to T cells and activating them
C) By secreting cytokines
D) By activating natural killer cells
Answer: B
40. What is the role of the thymus gland in T cell development?
A) Producing antibodies
B) Maturation and selection of T cells
C) Activation of B cells
D) Regulation of cytokine production
Answer: B
41. Which of the following is a function of cytotoxic T cells (CD8+ cells)?
A) Producing antibodies
B) Activating B cells
C) Killing infected cells
D) Initiating complement activation
Answer: C
42. How do allergens trigger allergic responses in susceptible individuals?
A) By activating T cells
B) By promoting immune tolerance
C) By inducing IgE-mediated mast cell activation
D) By suppressing antibody production
Answer: C
43. What is the significance of the secondary lymphoid organs in immune responses?
A) They produce red blood cells
B) They filter blood and remove pathogens
C) They facilitate immune cell interactions and responses
D) They regulate hormone production
Answer: C
44. How do effector T cells contribute to immune responses?
A) By recognizing self from non-self antigens
B) By secreting cytokines and directly killing infected cells
C) By activating B cells
D) By promoting immune tolerance
Answer: B
45. What is the role of Toll-like receptors (TLRs) in immune cell activation?
A) Recognizing self from non-self antigens
B) Activating natural killer cells
C) Recognizing pathogen-associated molecular patterns (PAMPs) and initiating immune responses
D) Initiating complement activation
Answer: C
46. Which of the following is a mechanism of immune evasion employed by pathogens?
A) Upregulation of MHC molecules
B) Activation of T regulatory cells (Tregs)
C) Inhibition of antigen presentation
D) Promotion of antibody production
Answer: C
47. What is the function of cytokine signaling pathways in immune cell communication?
A) Regulating hormone production
B) Initiating complement activation
C) Transmitting signals to coordinate immune responses
D) Inducing apoptosis in infected cells
Answer: C
48. How do genetic variations in MHC molecules influence immune responses?
A) They have no impact on immune recognition
B) They determine susceptibility to autoimmune diseases
C) They affect antigen presentation and immune cell activation
D) They regulate phagocytosis of pathogens
Answer: C
49. What is the role of antigen-specific tolerance in preventing autoimmune reactions?
A) It promotes immune cell activation
B) It inhibits immune responses against self-antigens
C) It triggers allergic reactions
D) It activates natural killer cells
Answer: B