Unit 1: Fundamentals of the immune system - Practice Quiz

1 Which type of immunity is present from birth and provides a rapid, non-specific first line of defense?

2 Immunity acquired through vaccination is an example of which type of immunity?

3 The transfer of antibodies from mother to fetus through the placenta is an example of:

4 All blood cells of the immune system originate from which type of cell?

5 The two main progenitor lineages derived from hematopoietic stem cells are the:

6 Which cells develop from the common lymphoid progenitor?

7 Which white blood cell is the most abundant and acts as a primary phagocyte in acute infection?

8 Which cell is primarily responsible for producing antibodies?

9 Which immune cell can kill virus-infected and tumor cells without prior sensitization?

10 Large phagocytic cells that also act as antigen-presenting cells are called:

11 In humans, T lymphocytes mature in which primary lymphoid organ?

12 In humans, B lymphocytes mature in which primary lymphoid organ?

13 What is the main function of primary lymphoid organs?

14 The clear fluid that circulates through the lymphatic vessels is called:

15 Which of the following is a major function of the lymphatic system?

16 Structures along lymphatic vessels that filter lymph and house immune cells are called:

17 Which organ filters the blood and is the largest secondary lymphoid organ?

18 What is the primary role of secondary lymphoid organs?

19 Which of the following is an example of a secondary lymphoid organ?

20 The humoral immune response is primarily mediated by which molecules?

21 A child receives an injection of tetanus antitoxin (preformed antibodies) after stepping on a rusty nail. This is an example of which type of immunity?

22 Which feature best distinguishes adaptive immunity from innate immunity?

23 Hematopoietic stem cells give rise to two main progenitor lineages. Which cell type is derived from the common myeloid progenitor?

24 A researcher isolates a progenitor cell that can develop into B cells, T cells, and NK cells but not into red blood cells. This cell is most likely a:

25 Which cell is considered the most effective professional antigen-presenting cell for activating naive T cells?

26 A patient's blood smear shows granulocytes with bilobed nuclei and large red-orange granules that increase during a parasitic worm infection. These cells are:

27 Which statement correctly matches an immune cell to its primary function?

28 In the thymus, developing T cells undergo positive and negative selection. What is the main purpose of negative selection?

29 Where do B lymphocytes complete their maturation in humans?

30 A child born with a congenitally absent thymus (DiGeorge syndrome) would most likely have a severe deficiency in which cell population?

31 Excess interstitial fluid that is collected by lymphatic vessels is called:

32 Into which structure does the thoracic duct ultimately drain its collected lymph?

33 Which of the following is a key function of the lymphatic system besides fluid balance?

34 The spleen filters blood and mounts immune responses. Which region of the spleen is primarily responsible for immune (lymphocyte) functions?

35 A pathogen enters through a cut on the hand. Antigen-presenting cells are most likely to activate lymphocytes in which secondary lymphoid organ?

36 Peyer's patches and tonsils are examples of which type of lymphoid tissue?

37 During a secondary humoral response, which antibody isotype predominates and why?

38 Which cell is the final differentiated effector cell that secretes large quantities of antibody?

39 The process by which the constant region of an antibody heavy chain changes (e.g., from IgM to IgA) without altering antigen specificity is called:

40 Neutralization is one effector function of antibodies. It works primarily by:

41 A newborn is protected against measles for the first few months of life due to maternal IgG transferred across the placenta. If the same infant later receives a live attenuated measles vaccine at 12 months, which combination correctly classifies these two events?

42 Why does passive immunity, such as administration of antivenom, provide immediate protection but no long-term memory, whereas active immunity is delayed but durable?

43 A patient with a mutation abolishing the transcription factor GATA-1 would most severely impair the development of which lineage from the common myeloid progenitor?

44 Both dendritic cells and lymphocytes can arise from more than one progenitor. Which statement about hematopoietic lineage commitment is correct?

45 A blood smear shows a granulocyte with a bilobed nucleus and large reddish-orange granules that stain with eosin. Elevated numbers of this cell are most characteristic of which condition?

46 Natural killer cells kill virus-infected cells that have downregulated MHC class I. Which principle best explains this targeting behavior?

47 Which cell type serves as the most potent professional antigen-presenting cell for activating naïve T cells, and why?

48 A child with DiGeorge syndrome has thymic aplasia. Which laboratory finding would you most expect?

49 During thymic selection, a developing thymocyte whose TCR binds self-peptide–MHC with intermediate affinity is allowed to survive. What is this process called and where does it predominantly occur?

50 Why does B cell development in the bone marrow include a 'receptor editing' checkpoint, and what does it accomplish?

51 Fluid filtered from capillaries that is not reabsorbed becomes lymph. Approximately how does the lymphatic system return this fluid to the circulation?

52 Lymph flow lacks a central pump yet moves unidirectionally. Which combination of mechanisms primarily drives lymph propulsion?

53 A patient who underwent splenectomy is at increased risk of overwhelming infection by encapsulated bacteria such as Streptococcus pneumoniae. What splenic function best explains this vulnerability?

54 In a lymph node, where do germinal centers form and what is the functional significance of this location?

55 MALT (mucosa-associated lymphoid tissue) differs from lymph nodes in a key structural feature. Which statement is correct?

56 During a secondary immune response to a T-dependent antigen, why is the antibody produced of higher affinity and predominantly IgG rather than IgM?

57 A polysaccharide vaccine given alone to a 6-month-old infant produces a weak, short-lived antibody response with no memory. Conjugating the polysaccharide to a protein carrier dramatically improves it. What is the immunological basis?

58 Which antibody isotype is most effective at agglutination and is the first secreted in a primary response, owing to its pentameric structure with ten antigen-binding sites?

59 A macrophage phagocytoses a bacterium coated with C3b and IgG. This coating enhances uptake through which combined mechanism?

60 Which scenario best illustrates the distinction between innate and adaptive immunity in terms of specificity and memory?