Adaptive Immunity: A Comprehensive Guide for Medical Students

Question 1

How do memory cells enhance the adaptive immune response upon subsequent pathogen encounters?

Accepted Answer

Provide a pool of pre-activated lymphocytes for rapid proliferation and differentiation into effector cells.

Answer

Produce antibodies with increased affinity for the specific antigen.

Answer

Eliminate the requirement for antigen presentation by antigen-presenting cells.

Answer

Suppress the activity of regulatory immune cells.

Question 2

Which immune cell type is responsible for producing antibodies?

Accepted Answer

B cells

Answer

T cells

Answer

Macrophages

Answer

Neutrophils

Question 3

What is the primary function of cytotoxic T cells?

Accepted Answer

Destroy virus-infected cells

Answer

Produce antibodies

Answer

Assist B cells in producing antibodies

Answer

Activate macrophages

Question 4

Which type of MHC molecule is found on the surface of all nucleated cells?

Accepted Answer

MHC I

Answer

MHC II

Answer

Both MHC I and MHC II

Answer

Neither MHC I nor MHC II

Question 5

What process involves genetic rearrangement in immature B cells to generate a diverse antibody repertoire?

Accepted Answer

V(D)J recombination

Answer

Somatic hypermutation

Answer

Clonal selection

Answer

Immunoglobulin class switching

Question 6

Which type of molecule recognizes and binds to specific antigens on pathogens?

Accepted Answer

Immunoglobulins

Answer

Cytokines

Answer

Interferons

Answer

Chemokines

Question 7

Which cytokine is essential for the differentiation of naive T cells into effector T cells?

Accepted Answer

Interleukin-2

Answer

Interleukin-4

Answer

Interferon-gamma

Answer

Tumor necrosis factor-alpha

Question 8

What is the primary role of dendritic cells in adaptive immunity?

Accepted Answer

Present antigens to T cells

Answer

Produce antibodies

Answer

Destroy pathogens

Answer

Activate B cells

Question 9

Which of the following immune cells is primarily responsible for producing antibodies?

Accepted Answer

B cells

Answer

T cells

Answer

Macrophages

Answer

Neutrophils

Question 10

What type of immune response involves the activation of T cells and the subsequent destruction of infected cells?

Accepted Answer

Cell-mediated response

Answer

Humoral response

Answer

Both humoral and cell-mediated responses

Answer

Neither humoral nor cell-mediated response

Question 11

Which of the following is NOT a class of antibodies?

Accepted Answer

IgF

Answer

IgG

Answer

IgA

Answer

IgM

Question 12

What is the primary function of the major histocompatibility complex (MHC)?

Accepted Answer

To recognize and present antigens to immune cells

Answer

To produce antibodies

Answer

To activate T cells

Answer

To destroy infected cells

Question 13

What is the primary role of cytokines in adaptive immunity?

Accepted Answer

To regulate immune cell activity

Answer

To produce antibodies

Answer

To recognize and destroy antigens

Answer

To activate complement

Question 14

What is the primary purpose of vaccination?

Accepted Answer

To stimulate the production of antibodies and provide immunity against specific pathogens

Answer

To treat existing infections

Answer

To suppress the immune system

Answer

To diagnose diseases

Question 15

What is the function of the thymus in the adaptive immune system?

Accepted Answer

Maturation and development of T cells

Answer

Production of antibodies

Answer

Recognition of pathogens

Answer

Destruction of infected cells

Question 16

Describe the pivotal role of the Major Histocompatibility Complex (MHC) in the activation of cytotoxic T cells.

Accepted Answer

MHC class I molecules bind processed antigens derived from the cytosol, presenting them to cytotoxic T cells.

Answer

MHC class II molecules bind unprocessed antigens from the extracellular environment, presenting them to helper T cells.

Answer

MHC molecules directly bind antigens from pathogens, presenting them to cytotoxic T cells.

Question 17

How do cytokines primarily regulate communication between immune cells during an adaptive immune response?

Accepted Answer

Binding to receptors on immune cells and triggering intracellular signaling

Answer

Directly activating immune cells

Answer

Enhancing the production of antibodies

Answer

Suppressing the activity of T cells

Question 18

Which of the following is NOT a characteristic of adaptive immunity?

Accepted Answer

Innate recognition of pathogens

Answer

High specificity

Answer

Memory response

Answer

Diversity of antigen recognition

Question 19

B cells primarily produce:

Accepted Answer

Antibodies

Answer

Cytokines

Answer

T cell receptors

Answer

Major histocompatibility complex molecules

Question 20

Which type of MHC molecule binds to CD4+ T cells?

Accepted Answer

MHC II

Answer

MHC I

Answer

MHC III

Answer

MHC IV

Question 21

Helper T cells (Th cells) primarily function to:

Accepted Answer

Activate B cells and macrophages

Answer

Secrete antibodies

Answer

Kill infected cells

Answer

Suppress immune responses

Question 22

Which of the following is NOT a type of antigen-presenting cell?

Accepted Answer

Platelet

Answer

Macrophage

Answer

Neutrophil

Answer

Dendritic cell

Question 23

The process by which antibodies bind to and inactivate antigens is known as:

Accepted Answer

Neutralization

Answer

Opsonization

Answer

Agglutination

Answer

Complement activation

Question 24

Which of the following cytokines is produced by Th2 cells and promotes antibody production?

Accepted Answer

Interleukin-4

Answer

Interferon-gamma

Answer

Interleukin-2

Answer

Tumor necrosis factor-alpha

Question 25

Discuss the various mechanisms by which antibodies neutralize pathogens and provide concrete examples for each mechanism.

Accepted Answer

Opsonization and phagocytosis

Accepted Answer

Neutralization of toxins

Accepted Answer

Complement activation

Accepted Answer

Antibody-dependent cell-mediated cytotoxicity (ADCC)

Question 26

How do regulatory T cells contribute to immune tolerance?

Accepted Answer

Suppressing excessive immune responses through anti-inflammatory cytokines

Answer

Activating B cells for antibody production

Answer

Eliminating activated T and B cells directly

Answer

Expressing cytotoxic molecules to suppress immune responses

Question 27

How do cytokines contribute to the adaptive immune response? Describe their roles in immune cell activation, differentiation, and regulation.

Accepted Answer

Cytokines are signaling molecules that regulate immune cell proliferation and differentiation, shaping the adaptive immune response.

Answer

Cytokines exclusively inhibit the activation of immune cells, suppressing their function.

Answer

Cytokines are produced solely by B cells, playing a limited role in immune cell communication.

Answer

Cytokines have no significant role in the adaptive immune response, as their functions are confined to innate immunity.

Question 28

How does the adaptive immune system differentiate between self and non-self molecules?

Accepted Answer

MHC-mediated presentation

Answer

Innate immune cell recognition

Answer

Antibody-antigen binding

Answer

Cytokine signaling

Question 29

In the adaptive immune response, which cell type is responsible for recognizing and binding to specific antigens?

Accepted Answer

T cells

Answer

Neutrophils

Answer

Macrophages

Answer

Eosinophils

Question 30

Which type of lymphocyte produces antibodies?

Accepted Answer

B cell

Answer

Macrophage

Answer

Natural killer cell

Answer

Eosinophil

Question 31

Which subset of T cells plays a central role in activating other immune cells?

Accepted Answer

T helper cell

Answer

Cytotoxic T cell

Answer

Regulatory T cell

Answer

Memory T cell

Question 32

Which class of antibodies is primarily involved in neutralizing extracellular bacteria and viruses?

Accepted Answer

IgG

Answer

IgM

Answer

IgE

Answer

IgA

Question 33

Which molecules present antigens bound to them on their surface, facilitating their recognition by T cells?

Accepted Answer

MHC molecules

Answer

Immunoglobulins

Answer

Complement proteins

Answer

Cytokines

Question 34

Which type of immunity involves antibodies and is effective against extracellular pathogens?

Accepted Answer

Humoral immunity

Answer

Cell-mediated immunity

Answer

Adaptive immunity

Answer

Innate immunity

Question 35

Which type of T cell directly kills infected cells?

Accepted Answer

Cytotoxic T cell

Answer

Helper T cell

Answer

Regulatory T cell

Answer

Memory T cell

Question 36

Which mechanism of immune tolerance involves the deletion of self-reactive T cells?

Accepted Answer

Clonal deletion

Answer

Antibody-mediated suppression

Answer

Suppression by regulatory T cells

Answer

Clonal anergy

Question 37

Which component of the adaptive immune system enhances opsonization and facilitates phagocytosis of pathogens?

Accepted Answer

Complement system

Answer

Cytokine network

Answer

Immunoglobulins

Answer

Antigen-presenting cells

Question 38

Which of the following immune cells produces antibodies?

Accepted Answer

B cells

Answer

Macrophages

Answer

Neutrophils

Answer

T cells

Question 39

What is the primary role of T cells in adaptive immunity?

Accepted Answer

To eliminate infected cells

Answer

To stimulate antibody production

Answer

To engulf pathogens

Answer

To directly neutralize toxins

Question 40

Which Major Histocompatibility Complex (MHC) molecule presents antigens to CD8+ T cells?

Accepted Answer

MHC class I

Answer

MHC class III

Answer

MHC class II

Answer

MHC class IV

Question 41

Which cytokine produced by Th1 cells activates macrophages?

Accepted Answer

IFN-γ

Answer

IL-10

Answer

TGF-β

Answer

IL-4

Question 42

Which vaccine type utilizes a weakened form of the infectious agent?

Accepted Answer

Live attenuated vaccine

Answer

Toxoid vaccine

Answer

Inactivated vaccine

Question 43

What process leads to the generation of plasma cells and memory cells from B cells?

Accepted Answer

Clonal expansion and differentiation

Answer

Isotype switching

Answer

Affinity maturation

Answer

Clonal deletion

Question 44

Which immune tolerance mechanism ensures immature T cells do not react against the body's own tissues?

Accepted Answer

Central tolerance

Answer

Immune surveillance

Answer

Inflammatory response

Answer

Peripheral tolerance

Question 45

What is the function of dendritic cells in the adaptive immune response?

Accepted Answer

Presenting antigens to T cells

Answer

Phagocytosing pathogens

Answer

Producing antibodies

Answer

Activating the complement system

Question 46

A 2-year-old boy presents with recurrent bacterial infections. Genetic testing reveals a deficiency in a specific type of immune cell characterized by its ability to produce antibodies. What type of cell is most likely deficient in this patient?

Accepted Answer

B cells

Answer

T cells

Answer

Natural Killer cells

Question 47

Which of the following is a primary function of helper T cells (Th cells) in the adaptive immune response?

Accepted Answer

Secrete cytokines to activate other immune cells

Answer

Directly kill infected cells by releasing cytotoxic granules

Answer

Phagocytize pathogens and present antigens

Question 48

A patient receives their first tetanus vaccine. What is the primary type of antibody produced during the initial immune response?

Accepted Answer

IgM

Answer

IgE

Answer

IgA

Answer

IgG

Question 49

Which of the following processes describes the mechanism by which antibodies prevent a virus from infecting a host cell?

Accepted Answer

Neutralization

Answer

Complement activation

Answer

Opsonization

Answer

Antibody-dependent cell-mediated cytotoxicity (ADCC)

Question 50

MHC class I molecules are found on:

Accepted Answer

All nucleated cells

Answer

Primarily on red blood cells

Answer

Exclusively on T cells

Answer

Only antigen-presenting cells (APCs)

Question 51

A patient presents with persistent fatigue, lymphadenopathy, and recurrent infections. Lab tests reveal a significantly reduced CD4+ T cell count. Which of the following conditions is most likely responsible?

Accepted Answer

HIV infection

Answer

Influenza

Answer

Tuberculosis

Answer

Common cold

Question 52

What type of immune response is characterized by a rapid and amplified reaction upon subsequent exposures to the same antigen?

Accepted Answer

Secondary immune response

Answer

Primary immune response

Answer

Innate immune response

Question 53

Which of the following cell types is responsible for destroying virally infected cells by inducing apoptosis?

Accepted Answer

Cytotoxic T cells

Answer

B cells

Answer

Helper T cells

Answer

Natural Killer cells

Question 54

The process by which B cells undergo changes to their antibody genes to produce antibodies with a higher affinity for a specific antigen is known as:

Accepted Answer

Affinity maturation

Answer

Clonal selection

Answer

Antigen presentation

Answer

Isotype switching

Question 55

Vaccines provide long-term protection against specific pathogens by inducing the formation of:

Accepted Answer

Memory cells

Answer

Antibodies

Answer

Cytokines

Answer

Antigens