Biochemistry Questions and Answers for Experienced people focuses on “Complementary Interactions Between Proteins and Ligands: The Immune System and Immunoglobulins”.
1. Which of the following is not the function of helper T cells is ____________
A. Produce soluble signaling proteins called cytokines, which include the interleukins
B. They help activate cytotoxic T cells to kill infected target cells
C. They help activate B cells to secrete antibodies and macrophages to destroy ingested microbes
D. They recognize and bind extracellular ligands
Answer: D
Clarification: The function of TH cells is to interact with macrophages and secrete cytokines that stimulate TC, TH and B cells to proliferate.
2. Which of the following is a function of Macrophages?
A. Ingest large particles and cells by phagocytes
B. Produce and secrete antibodies
C. Interact with infected host cells through receptors on T-cell surface
D. Interact with macrophages and secrete cytokines
Answer: A
Clarification: The remaining are the functions of B cells, TC and TH cells respectively.
3. Which of the following is a function of B lymphocytes?
A. Ingest large particles and cells by phagocytes
B. Produce and secrete antibodies
C. Interact with infected host cells through receptors on T-cell surface
D. Interact with macrophages and secrete cytokines
Answer: B
Clarification: The remaining are the functions of macrophages, TC and TH cells respectively.
4. Which of the following is a function of T lymphocytes?
A. Ingest large particles and cells by phagocytes
B. Produce and secrete antibodies
C. Interact with infected host cells through receptors on T-cell surface
D. Interact with macrophages and secrete cytokines
Answer: C
Clarification: The remaining are the functions of macrophages, B cells and TC respectively.
5. The most abundant immunoglobulin is ____________
A. IgA
B. IgE
C. IgG
D. IgM
Answer: C
Clarification: IgG is the most abundant antibody found in all body fluids.
6. Which of the following is the largest immunoglobulin?
A. IgA
B. IgE
C. IgG
D. IgM
Answer: D
Clarification: IgM is the largest pentameric type of antibody in the human circulatory system.
7. The antibody present in secretions like tears and saliva is ____________
A. IgA
B. IgE
C. IgG
D. IgM
Answer: A
Clarification: Secretory IgA is the main antibody present in mucous secretions and other secretions like tears and saliva.
8. Which of the following antibody first reaches the site of infection?
A. IgA
B. IgE
C. IgG
D. IgM
Answer: D
Clarification: IgM which is produced by B cells appears in response to the initial exposure to antigen.
9. Where do T-lymphocytes develop into fully competent but not activated T-cells?
A. The thymus gland
B. The lymph nodes
C. The thyroid gland
D. The bone marrow
Answer: A
Clarification: T cells are called so because they mature in the thymus gland.
10. Which of the following is true?
A. Most of the antibodies recognize small organic molecules
B. Most of the antibodies recognize proteins
C. Monoclonal antibodies produced in the laboratory lack the constant regions of IgG
D. IgM is a pentamer with 10 antigen binding sites
Answer: B
Clarification: Antibodies can recognize proteins like antigens.
11. IgG consists of ____________
A. A light chain and two heavy chains joined by a disulfide bond
B. Two light chains and a heavy chain joined by a disulfide bond
C. Two light chains and two heavy chains joined by a disulfide bond
D. Two light chains and two heavy chains joined by hydrogen bond
Answer: C
Clarification: IgG consists of 2 subunits including 2 heavy chains and 2 light chains.
12. Which of the following is a true statement?
A. IgG is involved in primary immune response
B. IgM is involved in primary immune response
C. IgG is involved only in secondary immune response
D. IgG and IgM both are involved in primary immune response
Answer: D
Clarification: IgG and IgM are involved in primary immune response.
13. The primary antibody of exocrine secretions is ____________
A. IgA
B. IgE
C. IgG
D. IgM
Answer: A
Clarification: IgA occurs in exocrine secretions and defends against bacteria cells and viruses.
14. Which of the following is not a feature of secondary immune respone to an antigen when compared to the first immune response to the same antigen?
A. Antibody is generated without T-cell help
B. Antibody is generated fast
C. Antibody produced has greater affinity for the antigen
D. Much antibody is produced
Answer: A
Clarification: The features of the secondary immune response are:
More antibodies are generated and the generation is fast.
Antibody produced has a greater affinity for the antigen.
15. Which of the following presents antigenic peptide to T-cells in order to initiate an adaptive immune response?
A. Plasma cell
B. Dendrite cell
C. Neutrophil
D. Epithelial cell
Answer: A
Clarification: Plasma cell is a fully differentiated B cell that produces antibody.
of Biochemistry for Experienced people, .