Explore topic-wise MCQs in Biochemistry.

This section includes 91 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.

51.

β-Lymphocytes are often called simply

A. B cells
B. T cells
C. T Lymphocytes
D. none of these
Answer» B. T cells
52.

Which species lack immunoglobulin light chains?

A. Camels
B. Humans
C. cows
D. Buffalo
Answer» B. Humans
53.

Which of the following are responsible for immune specificity?

A. Antigens
B. Antibodies
C. T lymphocytes
D. Macrophage
Answer» C. T lymphocytes
54.

Lack of reaction to our own human leukocyte antigens (HLAs) is known as?

A. autoimmunity
B. complement system
C. clonal selection
D. tolerance
Answer» E.
55.

The humoral immune response relies on the production of soluble proteins called

A. antibodies
B. macromolecules
C. lymphocytes
D. none of these
Answer» B. macromolecules
56.

Which of the following is most likely to produce anaphylaxis in a susceptible individual?

A. Pollen
B. Mold
C. Dust
D. Bee sting
Answer» E.
57.

A cell which defends against body cells in which viruses are reproducing is

A. Exotoxin
B. Cytotoxic T cell
C. Endotoxin
D. Suppressor T cell
Answer» C. Endotoxin
58.

Cleavage of an IgG molecule by a specific protease can produce

A. an antigen-binding site and two constant regions
B. two heavy chain-light chain dimers
C. an inactive mixture of oligopeptides
D. two Fab fragments and one Fc fragment
Answer» E.
59.

Which of those immunoglobulin classes is mainly found in external secretions?

A. Ig A
B. Ig D
C. Ig M
D. IgE
Answer» B. Ig D
60.

Papain digest IgG into

A. two Fab fragments and one Fc fragment
B. three Fab fragments and two Fc fragments
C. two Fab fragments and two Fc fragments
D. three Fab fragments and three Fc fragments
Answer» B. three Fab fragments and two Fc fragments
61.

Antibodies can be used

A. for the localization of proteins in the cell
B. for protein purification
C. to catalyze chemical reactions
D. all of the above
Answer» E.
62.

The protein, produced by B cells that binds to a specific antigen is

A. phagocyte
B. leukocyte
C. vaccine
D. antibody
Answer» E.
63.

Which of the following characteristics are common in lymphocytes, macrophages, and neutrophils?

A. They are all part of the nonspecific immune response in vertebrates
B. They are all part of the specific immune response in vertebrates
C. They are all part of the internal defenses of nonvertebrates
D. They are all types of white blood cells
Answer» E.
64.

Which of these is part of the lymphoid system in humans?

A. Liver
B. Stomach
C. Tonsils
D. Kidneys
Answer» D. Kidneys
65.

Antigenic determinants bind to which portions of an antibody?

A. Variable regions
B. Constant regions
C. Only light chains
D. Only heavy chains
Answer» B. Constant regions
66.

Structures of anti-PCP antibody shows that the tight binding of PCP to the antibody is primarily due to

A. hydrophobic forces
B. electrostatic forces.
C. Van der Waals forces.
D. none of these
Answer» B. electrostatic forces.
67.

What type of B cell is like a tiny factory that produces antibodies identical to the B cell receptor that bind to the original antigen?

A. T cells
B. Memory cells
C. Plasma cells
D. Macrophages
Answer» D. Macrophages
68.

Which of the following white blood cells act as scavengers when they engulf and digest pathogens?

A. Macrophages
B. T cells
C. B cells
D. Lymphocytes
Answer» B. T cells
69.

Which of the following components of the vertebrate immune response occurs first upon invasion by a virus or bacterium?

A. Activation of killer T lymphocytes
B. Activation of B lymphocytes
C. The inflammatory response
D. Mobilization of complement proteins
Answer» D. Mobilization of complement proteins
70.

The human IgG class of antibodies is divided into

A. five IgG classes
B. two IgG classes
C. three IgG classes
D. four IgG classes
Answer» E.
71.

Monoclonal refers to

A. a single clone of antibody-producing cells
B. all the antibody molecules which are identical
C. the binding with same antigenic site with identical binding affinities
D. all of the above
Answer» E.
72.

If Class IIMHC is not expressed in the thymus, the resulting immune deficiencies would include all of the following except reduced

A. alternative complement activation.
B. CD8 T cell-mediated cytotoxicity
C. macrophage activation to vesicular pathogens
D. IgG synthesis
Answer» B. CD8 T cell-mediated cytotoxicity
73.

Fab fragment has

A. one antigen binding site
B. two antigen binding site
C. one antibody binding site
D. two antibody binding site
Answer» B. two antigen binding site
74.

Immunological memory is due to

A. short lived macrophage that can recognize specific pathogens
B. long lived B cells that secrete a specific antibody
C. long lived B cells that secrete a specific antigen
D. short lived helper T cells that signal macrophage to divide
Answer» C. long lived B cells that secrete a specific antigen
75.

IgE provides

A. immunity against some parasites
B. complement killings of the cells and phagocytosis
C. secretions in the body
D. all of the above
Answer» B. complement killings of the cells and phagocytosis
76.

Which of the Rous sarcoma virus has a homologous cellular protein?

A. c-src
B. v-src
C. v-ha-src
D. v-ha-ras
Answer» B. v-src
77.

A monoclonal antibody (mAb) specific for the 2,4-dinitrophenyl (DNP) hapten might also bind

A. Leu or Ileu
B. His or Pro
C. Tyr or Phe
D. Ser or Thr
Answer» D. Ser or Thr
78.

The immunoglobulin fold is

A. found only in IgG molecules
B. a β-barrel composed of a three- and a four-stranded antiparallel β-sheet
C. both (a) and (b)
D. found six times in the IgG molecule
Answer» C. both (a) and (b)
79.

What is a protein produced by host cells infected by viruses?

A. Interferon
B. Histamine
C. Antiserum
D. Vaccine
Answer» B. Histamine
80.

Type A blood

A. can be used to donate to type AB individuals
B. can be used to donate to type B individuals
C. contains type B antigens on the surface of red blood cells
D. can always be used to donate to an Rh+ individual
Answer» B. can be used to donate to type B individuals
81.

Which of the following blood proteins can destroy pathogens?

A. Major histocompatibility complex
B. Platelets
C. Fibrinogen
D. Complement system
Answer» E.
82.

What is the behavior in which T cells and B cells constantly travel throughout the body seeking out and destroying foreign substances?

A. Antibody-mediated immune response
B. Immune surveillance
C. Cell-mediated immune response
D. Vaccination
Answer» C. Cell-mediated immune response
83.

What is the result of invasion of a body by pathogens?

A. Infection
B. Inflammation
C. Swelling
D. Pus
Answer» B. Inflammation
84.

Which of the following produces the antibodies employed in the specific immune response of vertebrates?

A. B lymphocytes
B. T lymphocytes
C. Neutrophils
D. Macrophages
Answer» B. T lymphocytes
85.

In a fetus, where are lymphocytes produced?

A. In the spleen
B. In the bone marrow
C. In the liver
D. In the heart
Answer» D. In the heart
86.

Which of the following is not part of the vertebrate immune system?

A. Lymphocytes
B. Antibodies
C. Cardiac glycosides
D. Lymph nodes
Answer» D. Lymph nodes
87.

In animals, blood clots serve the function of

A. consuming invading organisms
B. helping them match the background coloration of the habitat
C. stimulating production of killer T lymphocytes
D. repairing damage to the body wall
Answer» E.
88.

Which of these is a type of specific defense against pathogens?

A. Lymphocytes
B. Macrophages
C. Phagocytes
D. Leukocytes
Answer» B. Macrophages
89.

The maturation of T cells and the production of particular T cell receptors occurs in the

A. thyroid gland
B. thymus gland
C. testes
D. all of these
Answer» C. testes
90.

What type of B cell remains dormant in the body, but can respond rapidly if the same antigen appears again?

A. T cells
B. Memory cells
C. Plasma cells
D. Macrophages
Answer» C. Plasma cells
91.

Which of the following provide specific defense against viruses and bacteria?

A. T cells
B. B cells
C. Complement
D. inflammation
Answer» C. Complement