MCQ on Antibodies

• Antibodies are glycoproteins which are highly specific to specific antigens. 
• They are also known as Immunoglobulins (Igs), produced in response to antigenic stimulation. 
• Antibodies are produced by plasma cells which in turn are formed by B–lymphocytes. 
• The mature plasma cells produce antibodies at an extremely rapid rate i.e. about 2000 molecules per second.
• Antibody is a ‘Y’ shaped molecule. 
• Each immunoglobulin molecule is made up of four polypeptide chains. There are two heavy or H-chains and two light or L-chains. 
• The four polypeptide chains are held together by disulfide bonds (-s-s-) to form a ‘Y’ shaped structure. 
• The region holding together arms and stem of antibody, is termed as hinge. 
• Each chain of the antibody includes two distinct regions, the variable region and the constant region. 
• Variable regions constitute the antigen-binding site (paratope). This part of antibody recognizes and binds to the specific antigen to form an antigen-antibody complex.

Antibodies (Immunoglobulins) MCQ Questions: 

1. B cells that produce and release large amounts of antibody are called_________

(1) Plasma cells

(2) Neutrophils

(3) Basophils

(4) All of these

Answer: 1

2. Which leukocyte destroys bacteria by means of phagocytosis intracellular digestion and the secretion of bactericidal chemicals?

(1) Neutrophils

(2) Basophils

(3) T Cell

(4) B Cell

Answer: 1

3. Antibodies are__________

(1) prostaglandins

(2) steroids

(3) lipoproteins

(4) glycoproteins

Answer: 4

4. Synthesis of antibodies takes place by which of the following cells?

(1) Bone marrow cells

(2) T-cells

(3) B-cells

(4) Lymph

Answer: 3

5. The basic structure of antibodies are______

(1) Y-shaped

(2) X-shaped

(3) Linear

(4) Hyperbolic

Answer: 1

6. Interferons are

(1) antibiotic proteins

(2) antiviral proteins

(3) antigen proteins

(4) all of the above

Answer: 2

7. Which of the following antibody gives a primary immune reaction?

(1) IgG

(2) IgM

(3) IgA

(4) IgE

Answer: 2

8. Which of the following immunoglobulins makes the largest percentage in breast milk?

(1) IgM

(2) IgD

(3) IgG

(4) IgA

Answer: 4

9. Which of the following antibodies is predominantly present in tears, saliva and mucous___________

(1) IgM

(2) IgG

(3) IgE

(4) IgA

Answer: 4

10. Which of the following antibody is an important host defense against encapsulated bacteria?

(1) IgM

(2) IgG

(3) IgE

(4) IgA

Answer: 2

11. The class of antibodies, which can cross placenta is____________

(1) IgD

(2) IgA

(3) IgG

(4) IGM

Answer: 3

12. Name the class of immunoglobulin which has a pentameric structure?

(1) IgE

(2) IgG

(3) IgA

(4) IgM

Answer: 4

13. Which of the following immunoglobulin is the main host defense against parasitic infections?

(1) IgE

(2) IgG

(3) IgA

(4) IgM

Answer: 1

14. Which of the following antibody is an important host defense against encapsulated bacteria?

(1) IgG1

(2) IgG2

(3) IgG3

(4) IgG4

Answer: B

15. Who discovered the structure of immunoglobulin by treating it with beta-mercaptoethanol?

(1) Nisonoff

(2) Edelman

(3) Porter

(4) Whittekar

Answer: 2

16. Which of the following immunoglobulin is the most abundant immunoglobulin in newborns?

(1) IgA

(2) IgM

(3) IgG

(4) IgD

Answer: 3

17. The specificity of the binding is due to_______

(1) Specific chemical constitution of each antibody.

(2) Specific chemical constitution of each T cell.

(3) Both of these

(4) All of these

Answer: 1

18. Which of the following antibodies directly take part in the opsonization process?

(1) IgM

(2) IgG

(3) IgA

(4) IgE

Answer: 2

19. Which of the following is the most common circulating antibody?

(1) IgM

(2) IgG

(3) IgA

(4) IgE

Answer: 2

20. Which of the following amino acids is found in the hinge region?

(1) Alanine

(2) Aspargine

(3) Proline and cysteine

(4) Phenylalanine

Answer: 3

21. Name the class of immunoglobulin which takes part in hypersensitivity reaction?

(1) IgG

(2) IgE

(3) IgA

(4) IgM

Answer: 2

22. Primary role for antibodies in resistance to bacterial infection is_________

(1) Antibody dependent cell mediated cytotoxicity

(2) Lysis of infected host cells

(3) Activation of the alternative complement pathway

(4) Opsonisation for increased uptake by phagocytic cells

Answer: 4

23. What is another name for antibodies?

(1) Immunoglobulins

(2) Globulins

(3) Paraglobulins

(4) Epitope

Answer: 1

24. What part of an antibody molecule binds to its targeted antigen?

(1) An epitope

(2) An paratope

(3) Antigenic determinants

(4) Both (1) and (3)

Answer: 4

25. B cells mature in the while T cells mature in the_________

(1) Bone Marrow, Thymus

(2) Thymus, Bone Marrow

(3) Bone Marrow, Spleen

(4) Liver, kidney

Answer: 1

26. Which of the following immune cells are most effective at destroying intracellular pathogens______

(1) Natural killer

(2) T Cell

(3) B Cell

(4) Kidney Cells

Answer: 1

27. What are antibodies with high specificity that only detect one epitope called________

(1) Monoclonal

(2) Biclonal

(3) Pentaclonal

(4) Polyclonal

Answer: 1