Immune System(Microbiology ) Questions and Answers

Question 1.  Large parasites such as helminthes may be killed extracellularly by the action of
  1.    basophils
  2.    monocytes
  3.    eosinophils
  4.    neutrophils
Explanation:-
Answer: Option C. -> eosinophils

Question 2.  Passive immunization is done for
  1.    tuberculosis
  2.    diphtheria
  3.    enteric fever
  4.    all of these
Explanation:-
Answer: Option B. -> diphtheria

Question 3.  Which of the following is correct for CD8 T cells?
  1.    CD8 T cells only recognize virus-infected cells
  2.    CD8 T cell receptor recognizes epitopes that are also commonly recognized by B cells
  3.    In the thymus, CD8 T cells undergo positive selection only, whereas CD4 T cells undergo negative selection only
  4.    CD8 T cells can kill individual virus-infected cells in a contact dependent fashion
Explanation:-
Answer: Option D. -> CD8 T cells can kill individual virus-infected cells in a contact dependent fashion

Question 4.  Polymorphonuclear leukocytes (or PMNs)
  1.    can be attracted to the site of an infection following activation of complement
  2.    are derived from bone marrow stem cells
  3.    are a type of phagocyte that can engulf and kill bacteria
  4.    all of the above
Explanation:-
Answer: Option D. -> all of the above

Question 5.  Which of the following is correct for isoantigens?
  1.    They are antigens found in all members of different species
  2.    They are antigens found in some members of a species
  3.    They are antigens found in all members of a species
  4.    They are antigens found in some members of different species
Explanation:-
Answer: Option B. -> They are antigens found in some members of a species

Question 6.  Numerous antibodies can be prepared, against one antigen, each binds to unique epitopes. How is this antibody diversity generated?
  1.    By rearrangements of the DNA encoding the variable regions of the heavy and light chains
  2.    By the combination of different heavy and light chains that form the antigen binding site
  3.    Antibody proteins can physically change their shape to bind different epitopes
  4.    Both (a) and (b)
Explanation:-
Answer: Option D. -> Both (a) and (b)

Question 7.  Which of the following expresses CD3 surface antigen?
  1.    Granulocytes
  2.    T cells
  3.    Monocytes
  4.    B cells
Explanation:-
Answer: Option B. -> T cells

Question 8. . Treatment with bacterial endotoxins results blast formation in
  1.    B cells
  2.    T cells
  3.    monocytes
  4.    none of these
Explanation:-
Answer: Option A. -> B cells

Question 9. . Cytotoxic T-cells can be recognized by which of the following cell surface marker?
  1.    CD4
  2.    CD7
  3.    CD8
  4.    CD9
Explanation:-
Answer: Option C. -> CD8

Question 10.  Major Histo Compatibility Complex (MHC) is a collection of genes arrayed on
  1.    chromosome 21 in man, chromosome 6 in mice
  2.    chromosome 6 in man, chromosone 21 in mice
  3.    chromosome 17in man, chromosome 6 in mice
  4.    chromosome 6 in man, chromosome 17 in mice
Explanation:-
Answer: Option D. -> chromosome 6 in man, chromosome 17 in mice