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.

1.

Immunogenicity

A. depends on the ability of the native antigen to be presented by MHC
B. is usually a property of self antigens such as eye tissue
C. is not a property of antibodies
D. is not a property of haptens
Answer» E.
2.

Which of the following is incorrect with regard to antigen epitopes?

A. An epitope may be shared by two different antigens
B. A protein molecule usually contains multiple epitopes
C. B cells bind only processed antigen epitopes
D. Epitopes may be linear or assembled
Answer» D. Epitopes may be linear or assembled
3.

In cellular immunity, T lymphocytes are responsible for the recognition and killing of foreign invaders. The cells are

A. cytotoxic T lymphocytes (CTL)
B. killer T cells
C. both (a) and (b)
D. none of the above
Answer» D. none of the above
4.

X-linked hyper IgM syndrome, resulting in high levels of serum IgM and low levels of serum IgG, is caused by a defect in CD40L expression. The specific immune event that would be prevented by a defective CD40L would be

A. activation of B cells by T-independent antigens
B. failure of B cells to provide co-stimulation for Th2 activation
C. failure of Th2 cells to provide co-stimulation for B cell isotype switching
D. failure of Th2 cells to provide co-stimulation for B cell proliferation
Answer» D. failure of Th2 cells to provide co-stimulation for B cell proliferation
5.

If a person is vaccinated against a disease sometime in the past, which of the following is currently in your body?

A. The disease organism itself and antigens for the disease organism
B. A very high level of antibodies against the disease antigens
C. Memory B lymphocytes for the antigen of this disease organism
D. All of the above
Answer» E.
6.

An example of an immunodeficiency disorder is

A. thyroiditis
B. rheumatic fever
C. systemic lupus erythematosus
D. AIDS
Answer» E.
7.

Specific translocations are associated with

A. colon cancer
B. breast cancer
C. pancreatic cancer
D. some leukemias
Answer» E.
8.

The immune response to a booster vaccine is called a(n)

A. cellular response
B. innate response
C. primary response
D. secondary response
Answer» E.
9.

Chronic granulomatous disease results from a failure to perform oxidative burst. This deficiency would be most likely to interfere with

A. CTL killing of viruses
B. dendritic cell activation to become a mature APC
C. infected cell processing of virus peptides
D. macrophage intracellular killing of bacteria
Answer» E.
10.

Polysaccharides on the surface of infecting microorganisms can also activate complement directly in the absence of

A. antibody via the alternative pathway
B. antigen via the alternative pathway
C. antibody via metabolic pathway
D. none of the above
Answer» B. antigen via the alternative pathway
11.

Combined cellular and humoral immune deficiencies result from lack of all of the following except

A. a thymus
B. class II MHC
C. HIV infection of CD4+ T cells
D. transporter of antigen peptides (TAP)
Answer» E.
12.

Bone marrow given to an infant with SCID must

A. be irradiated to eliminate GVHD
B. contain mature T cells that can begin making immune responses immediately
C. come from a donor that shares some MHC alleles with the recipient
D. come from one of the child's parents
Answer» D. come from one of the child's parents
13.

The antibiotic penicillin is a small molecule that does not induce antibody formation. However, penicillin binds to serum proteins and forms a complex that in some people induces antibody formation resulting in an allergic reaction. Penicillin is therefore

A. an antigen
B. a hapten
C. an immunogen
D. both an antigen and a hapten
Answer» E.
14.

DiGeorge's syndrome is characterized by the lack of a thymus The mouse model closest to this human disease would be a

A. knock-out mouse for RAG-1 and RAG-2
B. knock-out mouse for a thymus
C. nude mouse
D. recombinant mouse for CD3
Answer» D. recombinant mouse for CD3
15.

A molecule that can be covalently linked to a non-immunogenic antigen to make it an immunogen is called a (n)

A. adjuvant
B. carrier
C. hapten
D. mitogen
Answer» C. hapten
16.

Infants are most susceptible to bacterial infection due to low circulating levels of IgG

A. in utero (before birth)
B. at 0-3 months of age
C. at 3-12 months of age
D. at 12-24 months of age
Answer» D. at 12-24 months of age
17.

What are the solutions prepared from weakened or dead microorganisms, viruses, or toxins that provide some immunity from diseases?

A. Vaccines
B. Histamines
C. Drugs
D. Antibiotics
Answer» B. Histamines
18.

What is the result of an abnormal response of the immune system to part of a person's own body?

A. Passive immunity
B. Cancer
C. An allergic response
D. An autoimmune disease
Answer» E.
19.

To detect a humoral immune response to influenza virus, it is possible to measure

A. cytotoxicity of virus-infected cells in tissue culture
B. dividing T cells in the draining lymph nodes
C. plasma cytokine levels
D. serum antibody titer
Answer» E.
20.

A selective IgA deficiency would be expected to result in problems with

A. bacterial infections
B. infections following dental work due to bacteria entering the bloodstream
C. mucosal pathogens
D. pathogens which can survive inside macrophages
Answer» D. pathogens which can survive inside macrophages
21.

The HIV virus infects primarily

A. brain cells
B. cells in the immune system
C. red blood cells
D. liver cells
Answer» C. red blood cells
22.

To elicit the best antibodies to mouse MHC I, it should be injected into a

A. goat
B. mouse of the same genetic background (strain)
C. mouse of a different strain
D. rat
Answer» B. mouse of the same genetic background (strain)
23.

Plasma cells produce thousands of __________ that are released into the bloodstream

A. antigens
B. antibodies
C. helper T cells
D. virus fragments
Answer» C. helper T cells
24.

The primary reason for AIDS, a deadly disease is that it

A. is caused by a virus
B. is caused by a bacterium
C. destroys key components of the body's internal defense system
D. causes a breakdown of the body's inflammatory response
Answer» D. causes a breakdown of the body's inflammatory response
25.

Very low doses of antigen may induce

A. hypersensitivity
B. immunological ignorance
C. low zone tolerance
D. low zone immunity
Answer» D. low zone immunity
26.

During exposure to a foreign invader, there are more __________ present in the vertebrate body than before exposure

A. antibodies
B. lymphocytes
C. macrophages and antigens
D. all of these
Answer» E.
27.

Which of the following is in the lymph nodes of a person battling a cold virus?

A. Huge numbers of white blood cells
B. Trapped viruses that have been roaming the body
C. Lymph ducts that enter and exit the nodes and Lymph fluid
D. All of the above
Answer» E.
28.

Retinoblastoma is due to a mutation in a

A. kinase
B. tumor supressor
C. cyclin
D. viral gene
Answer» C. cyclin
29.

Lymphocytes are activated by antigen in the

A. blood stream
B. bone marrow
C. liver
D. lymph nodes
Answer» E.
30.

A pathogen can be a (n)

A. agent that causes a disease
B. virus
C. bacteria
D. All of these
Answer» E.
31.

The ability of an antigen to induce an immune response does not depend on the antigen's

A. ability to enter the thyroid
B. degree of aggregation
C. dose
D. size
Answer» B. degree of aggregation
32.

For specific antigen recognition by T cells,

A. antigen is bound by a T cell membrane antibody
B. denaturation of antigen does not reduce epitope recognition
C. MHC molecules are not required
D. antigen exposure during T cell maturation is required
Answer» C. MHC molecules are not required
33.

A virus vaccine that can activate cytotoxic T cells must contain

A. a high dose of virus particles
B. an adjuvant to stimulate T cell division
C. live virus
D. virus peptides
Answer» D. virus peptides
34.

Antibodies bound to an invading microorganism activate the complement system via

A. classical pathway
B. metabolic pathway
C. Embden Meyerhof pathway
D. Entner-Doudoroff pathway
Answer» B. metabolic pathway
35.

Antigen, when injected in the body activates its specific lymphocytes in the

A. blood circulation
B. draining lymph nodes
C. MALT (mucosa associated
D. spleen lymphoid tissue
Answer» C. MALT (mucosa associated
36.

To treat HIV infections using drugs, the major problem is that

A. the drugs that are good inhibitors cannot by synthesized
B. the drugs interfere with normal digestion
C. the virus particles with altered (mutant) proteases arise
D. the drugs are rapidly degraded
Answer» D. the drugs are rapidly degraded
37.

CD antigens

A. allow leukocytes to recognize antigen
B. are each expressed on only one cell type
C. are expressed on immune cells to mark them for separation
D. function as receptors for cytokine and CAMs
Answer» E.
38.

Which of the following immune cells would have an especially low count in a patient with advanced AIDS?

A. Killer T lymphocytes
B. Helper T lymphocyte
C. B lymphocytes
D. None of these
Answer» C. B lymphocytes
39.

Difficulties with somatic gene therapy arise from all of the following except

A. GVHD caused by mature T cells in the transplanted cells
B. inserting a gene so that it will function properly
C. limited life span of more mature hematopoietic cells
D. transducing genetic material into stem cells
Answer» B. inserting a gene so that it will function properly
40.

An autoimmune disease is

A. AIDS
B. Measles
C. Lupus
D. Mumps
Answer» D. Mumps
41.

Antibodies in the human immune system can identify approximately 108 different molecules Which one of the following is correct?

A. This diversity is generated from 108 different immunoglobin genes
B. Many of these molecules are self-antigens
C. Most of these antibodies recognize proteins
D. Most of these antibodies recognize small organic molecules
Answer» D. Most of these antibodies recognize small organic molecules
42.

A polyclonal antibody response

A. is produced only in response to polymeric antigens
B. is produced by several B cells recognizing different pitopes on the same antigen
C. occurs during the lag phase of the immune response
D. violates clonal selection
Answer» C. occurs during the lag phase of the immune response
43.

Monoclonal antibodies were first produced by

A. Georges Kohler and Cesar Milstein
B. Sarkar and Sommer
C. Selman Waksman
D. Edward Jenner and Louis Pasteur
Answer» B. Sarkar and Sommer
44.

During the lag period between antigen contact and detection of adaptive immunity,

A. antigen is hidden from the immune system in macrophages
B. innate immune effectors are eliminating antigen
C. innate immunity blocks the activation of adaptive immune effector cells
D. new B and T cells with the appropriate antigen specificity must be produced in the bone marrow
Answer» C. innate immunity blocks the activation of adaptive immune effector cells
45.

Each IgA antibody molecule consists of

A. four polypeptide chain and has two antigen binding site
B. two polypeptide chain and has one antigen binding site
C. three polypeptide chain and has two antigen binding site
D. two polypeptide chain and has two antigen binding site
Answer» B. two polypeptide chain and has one antigen binding site
46.

The chemical, typically released by the body in an allergic response is

A. histamine
B. allergens
C. antihistamines
D. perforins
Answer» B. allergens
47.

Alum is an effective adjuvant because it

A. disaggregates the antigen.
B. is immunogenic for stem cells
C. is immunogenic for T cells
D. slows the release of antigen
Answer» D. slows the release of antigen
48.

The main function of antibodies is to

A. kill all the foreign bodies
B. generate antigens, thus conferring immunization
C. protect the circulatory system
D. chemically combine with the antigen which induces it, inactivate the antigen and protect the body from disease
Answer» E.
49.

A secondary antibody is an antibody that

A. has been used in prior experiments
B. is synthetically produced
C. binds to another antibody
D. is produced in boostered animals
Answer» D. is produced in boostered animals
50.

Antibodies of the IgG class

A. consist of four subunits
B. are glycoproteins
C. are secreted into the bloodstream
D. all of the above
Answer» E.