Immunology: Immunoglobulin Structure, Function: MCQ

Multiple Choice Question on Immunoglobulin Structure, Function

1) Immunoglobulin is the plasma protein that specifically binds to antigens. Identify the region of electrophoresis that consists of these major immunoglobulins.

a) Alpha region
b) Beta region
c) Gamma region
d) None of the above

2) The five classes of immunoglobulin include the following, except?
a) IgA
b) IgD
c) IgE
d) IgH

3) Which of the following class of immunoglobulin is pentameric structure?
a) IgA
b) IgD
c) IgH
d) IgM

4) Which of the following class of immunoglobulin is dimeric structure?
a) IgA
b) IgD
c) IgH
d) IgM

5) The IgA and IgMs consist of which of the following chain can allow its polymerization?
a) H chain
b) L chain
c) J chain
d) V chain

6) The monomeric immunoglobulin consists of heterodimers of heavy (H) and light (L) chains bound together by non-covalent interaction and disulfide bonds. 
Which of the following is the antigen-binding site?
a) Fab
b) Fc
c) Hinge region
d) None of the above

7) The hinge region of the immunoglobulin consists of the disulfide bond that held the heterotetramer together. Also, it contributes to the flexibility of the antibody chain. 
Which of the following antibody class do not have a hinge region?
a) IgA
b) IgD
c) IgE
d) IgG

8) The hypervariable complementarity determining region is responsible for which of the following function?
a) binding to antigen
b) binding to FcR
c) binding to complement
d) None of the above

9) Identify the protease that results in two different fragments of antibodies namely Fab and Fc fragments as shown in the figure below:

a) Pepsin
b) Trypsin
c) Papain
d) Fucin

10) Identify the protease that results in two different fragments of antibodies namely Fab and Fc fragments as shown in the figure below:

a) Pepsin
b) Trypsin
c) Papain
d) Fucin

11) The variable heavy and light chain makes up the antigen recognition region which consists of six complementarity determining regions (CDRs) (three from each heavy and light chain). 
In addition, a stretch of amino acid sequence also known as the framework region...................................
a) assist in the recognition of antigen
b) act as a scaffold to support CDR
c) are highly variable
d) None of the above

12) The variable heavy and light chains make up the antigen recognition region.
Which of the following is mostly involved in antigen binding?
a) Variable light chain
b) Variable heavy chain
c) Both of the above
d) None of the above

13) The contact area of the antigen binding area may consist of the protrusion or depression that complementarity matches the antigen. 
This contact area span approximately ............................. based on well-studied Lysozyme/anti-Lysozyme interaction.
a) 15-22 amino acids
b) 5-12 amino acids
c) 25-60 amino acids
d) None of the above

14) The antigen-antibody interactions are considered inducible which means
a) The antigen binding site has performed a site that exactly fits the antigen.
d) The antigen binding site is rigid
c) The antigen binding site undergoes conformation changes after contact with the antigen
d) None of the above

15) Which of the following antibody have four constant regions (CH1, CH2, CH3, CH4)?
a) IgA
b) IgD
c) IgG
d) IgM

16) The effector function of the antibody requires its Fc region. The Fc region binds to cells or proteins to mediate its function. 
Which of the following is the effector function of the antibody?
a) Antigen binding to antibody promotes opsonization
b) Antigen binding to antibody activates complement
c) Antigen binding to antibody activates cell cytotoxicity
d) All of the above

17) Which of the following immunoglobulins are secretory and present in the milk?
a) IgG
b) IgM
c) IgA
d) IgE

18) The receptor that is responsible for the transport of IgAs across the epithelial barriers:
a) Poly Fc receptor
b) Poly Ig receptor
c) Poly Fab receptor
d) All of the above

19) Which of the following antibody is produced as a primary immune response and have higher valency to remove clear antigens?
a) IgM
b) IgG
c) IgA
d) IgE

20) Which of the following is the passive immunity transferred from the mother to its offspring?
a) Transplacental transfer of IgGs
b) Transfer of IgAs in the milk
c) Both a & b
d) None of the above

21) Which of the following antigen-bound antibodies bind to the Fc receptor present on the basophils and tissue mast cells, and release various pharmacoactive mediators involved in anaphylaxis?
a) IgA
b) IgD
c) IgM
d) IgE

22) The Fc receptor is a plasma membrane glycoprotein that binds to different immunoglobulin and triggers effective functions. 
Which of the following Fc receptor is involved in the transfer of IgG from mother to fetus?
a) Fc€R
b) FcRN
c) FcµR
d) FcγR

23) The immunoglobulin superfamily is the group of membrane proteins that possess one or more homologous immunoglobulin domains. 
Which of the following is NOT an immunoglobulin superfamily?
a) T cell receptor
b) beta2 microglobulin
c) Insulin receptor
d) Platelet-derived growth factor

24) B-cell receptors consist of membrane-bound immunoglobulin and a small heterodimer protein required for signaling. 
Which of the following is the heterodimer protein?
a) Igα & Igβ
b) Igµ & Igγ
c) Igα & Igγ
d) None of the Above

25) Multiple Myeloma is characterized by excessive production of immunoglobulin and the presence of a light chain in urine. 
Which of the following cells are responsible for the production of immunoglobulin?
a) T cells
b) Plasma cells
c) B-cells
d) Dendritic cells

26) Which of the following complement is bound by IgG?
a) C2a
b) C2b
c) C3a
d) C3b

27) Which of the following subclass of IgG molecule is the most potent activator of the complement pathway?
a) IgG1
b) IgG2
c) IgG3
d) IgG4

28) Which of the following subclass of IgG does not readily cross the placental barriers?
a) IgG1
b) IgG2
c) IgG3
d) IgG4

29) Which of the immunoglobulin isotype have the shortest half-life?
a) IgG
b) IgM
c) IgA
d) IgE

30) Which of the immunoglobulin isotype have the longest half-life?
a) IgG
b) IgM
c) IgA
d) IgE


Multiple Choice Answers:
1-c)Gamma region 
2-d)IgH 
3-d)IgM
4-a)IgA
5-c)J chain
6-a)Fab
7-c) IgE
8-a) binding to antigen
9-c) Papain
10-a)Pepsin
11-b)act as a scaffold to support CDR
12-b)
13-a) 15-22 amino acids
14-c) 
15-d) IgM
16-d)
17-c) IgA
18-b)Poly Ig receptor 
19-a)IgM
 20-b)Transfer of IgAs in the milk
21-d)IgE
 22)-,
23-c) Insulin receptor
24-a)Igα & Igβ 
25-b)Plasma cells
26-d)C3b
27-c)IgG3
28-b)IgG2
29-d)IgE
30-a)IgG

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