Major Histocompatibility Complex (MHC): Interactive Learning Quizzes

Question 1

Which of the following is a primary function of MHC molecules?

Accepted Answer

Antigen presentation

Answer

Protein degradation

Answer

Signal transduction

Answer

Hormone secretion

Question 2

The peptide-binding groove of MHC class I molecules is primarily composed of which type of structural element?

Accepted Answer

Alpha helices

Answer

Beta sheets

Answer

Disulfide bonds

Answer

Glycoproteins

Question 3

Which of the following cells is responsible for presenting antigens to CD8+ T cells?

Accepted Answer

Dendritic cells

Answer

B cells

Answer

Macrophages

Answer

Neutrophils

Question 4

Which of the following techniques is commonly used to identify MHC alleles?

Accepted Answer

Polymerase chain reaction (PCR)

Answer

Flow cytometry

Answer

Immunohistochemistry

Answer

Western blotting

Question 5

The primary function of MHC molecules is to:

Accepted Answer

Present antigens to immune cells

Answer

Regulate T cell activity

Answer

Produce antibodies

Answer

Mediate cell-mediated immunity

Question 6

MHC class I molecules present antigens to which type of immune cell?

Accepted Answer

Cytotoxic T cells

Answer

Helper T cells

Answer

B cells

Answer

Macrophages

Question 7

A characteristic feature of MHC molecules is:

Accepted Answer

Polymorphism

Answer

Monomorphism

Answer

High mutation rate

Answer

Low expression levels

Question 8

Which disease is strongly linked to MHC haplotypes?

Accepted Answer

Ankylosing spondylitis

Answer

Asthma

Answer

Alzheimer's disease

Answer

Influenza

Question 9

MHC-peptide complexes are recognized by T cell receptors (TCRs) during:

Accepted Answer

Cell-mediated immunity

Answer

Humoral immunity

Answer

Innate immunity

Answer

Adaptive immunity

Question 10

Which technique is used to match MHC haplotypes for organ transplantation?

Accepted Answer

Polymerase chain reaction (PCR)

Answer

Flow cytometry

Answer

Enzyme-linked immunosorbent assay (ELISA)

Answer

Western blotting

Question 11

Which of the following does NOT influence the expression of MHC molecules?

Accepted Answer

Age

Answer

Genetic factors

Answer

Cytokine stimulation

Answer

Viral infection

Question 12

Which of the following cell types is NOT involved in the presentation of antigens to T cells?

Accepted Answer

Neutrophils

Answer

Dendritic cells

Answer

Macrophages

Answer

B cells

Question 13

Which MHC class is responsible for presenting antigens to CD8+ cytotoxic T cells?

Accepted Answer

MHC Class I

Answer

MHC Class II

Answer

MHC Class III

Question 14

What is the primary function of the beta-2-microglobulin (β2M) protein?

Accepted Answer

MHC stabilization

Answer

Antigen binding

Answer

T cell activation

Answer

Cytokine production

Question 15

What is the primary role of polymorphic MHC molecules in immune responses?

Accepted Answer

Antigen discrimination

Answer

Signal transduction

Answer

Immunosuppression

Answer

Cytokine secretion

Question 16

Which of the following is a potential consequence of MHC mismatching in organ transplantation?

Accepted Answer

Rejection

Answer

Autoimmunity

Answer

Allergic reaction

Answer

Anaphylaxis

Question 17

What is the primary genetic mechanism behind MHC diversity?

Accepted Answer

Recombination

Answer

Mutation

Answer

Gene duplication

Answer

Epigenetic regulation

Question 18

How does diversity within the Major Histocompatibility Complex (MHC) impact the progression and treatment of infectious diseases?

Accepted Answer

MHC diversity influences personalized treatment approaches.

Answer

MHC diversity does not influence disease outcomes.

Answer

MHC diversity only affects the severity of infectious diseases.

Question 19

How does MHC restriction ensure the specificity and tolerance of adaptive immune responses?

Accepted Answer

MHC restriction limits T cell activation to antigens presented on self-MHC molecules, preventing attacks on self-antigens and promoting tolerance.

Answer

MHC restriction allows T cells to recognize a wide range of antigens by presenting them on various MHC molecules.

Answer

MHC restriction aids B cell differentiation into plasma cells and antibody production.

Answer

MHC restriction has no significant role in immune responses.

Question 20

How do MHC haplotypes influence an individual's risk of developing autoimmune diseases?

Accepted Answer

MHC haplotypes affect antigen presentation, impacting T cell responses and self-non-self discrimination.

Answer

MHC haplotypes regulate cytokine production, influencing the immune response.

Answer

MHC haplotypes determine antibody specificity.

Answer

MHC haplotypes have no role in autoimmune susceptibility.

Question 21

What is the primary responsibility of Major Histocompatibility Complex (MHC) molecules?

Accepted Answer

Recognizing and presenting antigens to immune cells

Answer

Producing cytokines and immunoglobulins

Answer

Engaging in cell-mediated cytotoxicity

Answer

Regulating gene expression

Question 22

Which type of MHC molecule presents antigens to CD8+ T cells?

Accepted Answer

MHC-I

Answer

MHC-II

Answer

MHC-III

Answer

MHC-IV

Question 23

What is the primary purpose of the polymorphic peptide-binding groove in MHC molecules?

Accepted Answer

To bind with specific peptides for antigen presentation

Answer

To facilitate recognition by antibodies

Answer

To signal to neighboring immune cells

Answer

To anchor the MHC molecule to the cell surface

Question 24

Which technique is commonly utilized to analyze MHC molecules on cell surfaces?

Accepted Answer

Flow cytometry

Answer

Immunohistochemistry

Answer

Western blotting

Answer

ELISA

Question 25

How do MHC molecules facilitate immune surveillance, allowing the immune system to identify and eliminate abnormal cells?

Accepted Answer

MHC molecules present antigens from abnormal cells to cytotoxic T cells, triggering their activation and destruction of the abnormal cells.

Answer

MHC molecules directly bind to abnormal cells and neutralize their activity.

Answer

MHC molecules secrete antibodies that target and destroy abnormal cells.

Answer

MHC molecules have no role in immune surveillance.

Question 26

MHC class I molecules present antigens to which type of T cells?

Accepted Answer

CD8+ T cells

Answer

CD4+ T cells

Answer

Natural killer cells

Answer

B cells

Question 27

Which of the following is NOT a characteristic of MHC class II molecules?

Accepted Answer

Present antigens to CD8+ T cells

Answer

Expressed on professional antigen-presenting cells

Answer

Bind to peptides derived from intracellular proteins

Answer

Involved in immune activation

Question 28

Antigen binding to MHC molecules is a key step in:

Accepted Answer

Antigen presentation

Answer

Antigen processing

Answer

Antigen recognition

Answer

Immune tolerance

Question 29

Central tolerance involves the:

Accepted Answer

Elimination of autoreactive T cells in the thymus

Answer

Inhibition of T cell activation in the periphery

Answer

Suppression of B cell responses

Answer

Induction of anergy in T cells

Question 30

The main function of MHC class I molecules is to:

Accepted Answer

Present antigens to CD8+ cytotoxic T cells

Answer

Present antigens to CD4+ helper T cells

Answer

Regulate immune responses

Answer

Activate B cells

Question 31

Which polymorphic gene cluster encodes MHC class II molecules?

Accepted Answer

HLA-DR, HLA-DQ, HLA-DP

Answer

HLA-A, HLA-B, HLA-C

Answer

HLA-E, HLA-F, HLA-G

Answer

MICA, MICB, HLA-6

Question 32

How are MHC molecules primarily loaded with antigens?

Accepted Answer

Proteasomal degradation

Answer

Endocytosis

Answer

Exocytosis

Answer

Lysosomal degradation

Question 33

In transplantation, MHC polymorphism can increase the risk of:

Accepted Answer

Graft rejection

Answer

Graft acceptance

Answer

Delayed graft function

Answer

Infection

Question 34

What is the main role of the cytoplasmic tail of MHC molecules in the process of antigen presentation?

Accepted Answer

Both A and B, as the cytoplasmic tail of MHC molecules plays dual roles in anchoring and signaling

Answer

Anchoring MHC molecules to the cell membrane, ensuring their stable expression on the cell surface

Answer

Interacting with intracellular signaling molecules, facilitating the communication between the antigen-presenting cell and other immune cells

Answer

Targeting MHC molecules for degradation, regulating their turnover and preventing their accumulation on the cell surface

Question 35

Which of the following is the primary function of the Major Histocompatibility Complex (MHC)?

Accepted Answer

To recognize and present antigens (pieces of foreign molecules) to immune cells, initiating an immune response

Answer

To produce antibodies against pathogens, directly targeting and neutralizing infectious agents

Answer

To directly kill infected cells, eliminating them from the body

Answer

To regulate the immune response, controlling the magnitude and duration of immune reactions

Question 36

Which of the following characteristics is unique to MHC class I molecules?

Accepted Answer

All of the above, as MHC class I molecules possess a combination of these distinctive features

Answer

They present antigens derived from intracellular pathogens, such as viruses and bacteria that have infected the cell

Answer

They are expressed on all nucleated cells in the body, ensuring widespread antigen presentation

Answer

They bind to CD8+ T cells, a type of cytotoxic T cell that can directly kill infected cells

Question 37

What is the name of the genetic region that is responsible for encoding MHC molecules?

Accepted Answer

Human Leukocyte Antigen (HLA) region, which is located on chromosome 6 and contains the genes that encode MHC molecules

Answer

Major Histocompatibility Region (MHR), an outdated term that was previously used to refer to the genetic region encoding MHC molecules

Answer

Immunoglobulin Gene Region (IGR), which encodes antibodies and is located on a different chromosome

Answer

T-cell Receptor Gene Region (TCRR), which encodes T-cell receptors and is located on a different chromosome

Question 38

What is the primary function of the peptide-binding groove in MHC molecules?

Accepted Answer

To bind and present antigens to T cells, allowing the T cells to recognize and respond to the antigen

Answer

To stabilize the MHC molecule, ensuring its proper folding and expression on the cell surface

Answer

To interact with other immune cells, facilitating communication and coordination of immune responses

Answer

None of the above, as the peptide-binding groove does not play a direct role in any of these functions

Question 39

Which type of immune response is primarily mediated by MHC class II molecules?

Accepted Answer

Humoral immunity, which involves the production of antibodies that can neutralize pathogens and activate other immune cells

Answer

Cell-mediated immunity, which involves the activation of cytotoxic T cells that can directly kill infected cells

Answer

Innate immunity, which provides a rapid and non-specific response to pathogens

Answer

Passive immunity, which is acquired from another individual, such as through the transfer of antibodies

Question 40

Which of the following is a primary function of Major Histocompatibility Complex (MHC) molecules?

Accepted Answer

Antigen presentation

Answer

Cell signaling

Answer

Ion transport

Answer

Hormone secretion

Question 41

What is the role of the T Cell Receptor (TCR) in the MHC-mediated antigen presentation process?

Accepted Answer

Recognizing MHC-peptide complexes

Answer

Killing target cells

Answer

Secreting cytokines

Answer

Producing antibodies

Question 42

What is the primary role of MHC class II molecules?

Accepted Answer

Presenting antigens to CD4+ T cells

Answer

Suppressing immune responses

Answer

Presenting antigens to CD8+ T cells

Answer

Activating B cells

Question 43

Which of the following is an advantage of MHC polymorphism?

Accepted Answer

Enhanced diversity of antigen recognition

Answer

Lowered transplant compatibility

Answer

Increased susceptibility to infections

Answer

Reduced risk of autoimmune diseases

Question 44

What is the genetic mechanism responsible for the inheritance of MHC alleles?

Accepted Answer

Codominant expression

Answer

Recessive inheritance

Answer

Incomplete dominance

Answer

Epigenetic regulation

Question 45

Which cells in the body constitutively express MHC class I molecules?

Accepted Answer

All nucleated cells

Answer

B cells only

Answer

Macrophages only

Answer

T cells only

Question 46

What is the term for the process by which peptides are loaded onto MHC molecules?

Accepted Answer

Antigen processing

Answer

Antigen recognition

Answer

Antigen presentation

Answer

Antigen degradation

Question 47

Which of the following cell types **lacks** MHC class I molecule expression?

Accepted Answer

Erythrocytes

Answer

B lymphocytes

Answer

Dendritic cells

Answer

Macrophages

Question 48

What is the primary function of MHC molecules in the immune system?

Accepted Answer

Presenting processed antigens to T cells

Answer

Directly neutralizing pathogens

Answer

Producing antibodies against specific antigens

Answer

Initiating the complement cascade

Question 49

Which MHC class primarily presents antigens derived from pathogens that have been engulfed and processed within cells?

Accepted Answer

MHC class II

Answer

Both MHC class I and II

Answer

MHC class III

Answer

MHC class I

Question 50

A mutation affecting the peptide-binding groove of an MHC class I molecule would most likely lead to:

Accepted Answer

Impaired recognition of the MHC-peptide complex by cytotoxic T cells

Answer

Enhanced antigen presentation to helper T cells

Answer

Increased susceptibility to autoimmune diseases

Question 51

Polymorphism in MHC genes is significant because it:

Accepted Answer

Increases the diversity of immune responses within a population, enhancing disease resistance

Answer

Increases the likelihood of autoimmune reactions

Answer

Reduces the effectiveness of vaccinations

Question 52

Which statement accurately reflects the role of MHC in transplantation?

Accepted Answer

MHC matching between donor and recipient is crucial for minimizing graft rejection

Answer

Immunosuppressive drugs can completely eliminate the risk of graft rejection, regardless of MHC compatibility

Answer

MHC molecules play a minor role in transplant rejection

Question 53

Which cell type is MOST effective in presenting antigens on MHC class II molecules to activate naive T cells?

Accepted Answer

Dendritic cells

Answer

Neutrophils

Answer

B cells

Answer

Macrophages

Question 54

Bare lymphocyte syndrome type II is a rare immunodeficiency caused by a defect in:

Accepted Answer

MHC class II expression

Answer

Antibody production

Answer

T cell receptor development

Answer

Complement activation

Question 55

Certain viruses evade the immune system by:

Accepted Answer

Downregulating MHC expression on infected cells, preventing recognition by cytotoxic T cells

Answer

Presenting viral antigens directly to B cells

Answer

Increasing the diversity of MHC molecules on the cell surface

Answer

Enhancing MHC class II expression to induce tolerance

Question 56

Monoclonal antibodies that block specific MHC molecules are a potential therapeutic strategy for:

Accepted Answer

Treating autoimmune diseases by interfering with self-antigen presentation

Answer

Boosting vaccine efficacy

Answer

Preventing viral infections

Answer

Enhancing antibody production