Chapter 16 mastering questions

Which of the following is NOT part of MALT?

lymphoid tissue in the respiratory tract
Peyer’s patches
the appendix
the spleen

While the spleen is a secondary lymphoid organ, it is separate from MALT, which includes the appendix, Peyer’s patches, and lymphoid tissues in the respiratory tract, vagina, urinary bladder, and mammary glands, because it filters blood instead of lymph.

The function of Th lymphocytes at the immunological synapse is to __________.

limit the synapse
remember the synapse
eliminate the synapse
strengthen the synapse

strengthen the synapse. Th lymphocytes function in part to help stabilize an already-formed immunological synapse by binding to the APC using its own TCR.

T-independent humoral immunity may be stunted in children because __________.
the repertoire of T cells in children is not fully developed
Th cells are overactive in children
the repertoire of B cells in children is not fully developed
children have a weak ability to produce tumor necrosis factor

the repertoire of B cells in children is not fully developed. Effective T-independent humoral immunity depends upon a fully developed and plentiful number of B cells. This is not the case in children, so they are more susceptible to diseases caused by pathogens with T-independent antigens.

Which of the following does NOT contain MHC II on its surface?
red blood cell
macrophage
lymphocyte
dendritic cell

Red blood cells do not serve as antigen-presenting cells, so they do not express MHC class II molecules.

IL-2 is involved in __________ Tc cells.
self-stimulation of
clonal deletion of
antigen presentation to
clonal expansion of

self-stimulation of

T-independent humoral immunity __________.
can be stimulated by any kind of antigen
is rapid
lasts a long time
induces strong immunological memory

is rapid. The speed of T-independent humoral immunity is similar to that of innate immunity, but it is relatively weak, does not last very long, and can be stimulated only by certain types of antigens.

Which of the following is the most variable region of an antibody molecule?
Fab region
Fc region
hinge region
None of the list responses is correct.

The Fab region (fragment, antigen binding) is, by definition, the most variable region of the antibody molecule, since it is the part of the molecule that interacts with and binds to antigens.

What is the role of helper T cells in the adaptive immune response?
Helper T cells activate B cells and cytotoxic T lymphocytes to kill infected host cells.
Helper T cells directly kill infected host cells.
Helper T cells produce and secrete antibodies.
Helper T cells phagocytize bacteria and viruses.

Helper T cells activate B cells that are displaying antigen, causing clonal expansion. Helper T cells also activate cytotoxic T cells, which will search for and destroy infected host cells.

What is meant by the clonal expansion of a B cell?
An activated B cell divides into cells that give rise to memory B cells and plasma cells.
An activated B cell will immediately begin to produce antibodies.
An activated B cell will engulf and digest anything foreign.
An activated B cell will kill infected host cells.

The activated B cell divides until there are many clones. Some differentiate into memory cells, other become plasma cells that produce and secrete antibodies.

The student who caught the cold caused by this specific Rhinovirus was exposed to the exact same Rhinovirus 18 months later. What component of the immune system will protect her from getting the same cold again?
Memory B cells
Antibodies that are "left over" from the last infection
Plasma cells
Dendritic cells

Memory cells to that specific virus are stored in the lymph nodes for many years. When the student comes into contact with this specific Rhinovirus, these memory cells quickly divide and differentiate into antibody-producing plasma cells. The antibodies will prevent the virus from reaching an infectious titer (number that causes infection).

Correctly order the steps involved cellular immunity:
The Tc recognizes the infected host cell
The Tc interacts with epitope presented by MHC-I on the dendritic cell
The Tc secretes perforin and granzyme, causing apoptosis
The helper T cell activates the Tc cell

The Tc interacts with epitope, The helper T cell activates the Tc cell, The Tc recognizes the infected host cell, The Tc secretes perforin and granzyme, causing apoptosis

Which of the following is NOT a step used by cytotoxic T cells to kill infected host cells?
Recognition of infected host cell using its TCR
Secretion of granzyme
Recognition of infected host cell using its CD4 glycoprotein
Secretion of perforin

Recognition of infected host cell using its CD4 glycoprotein. The cytotoxic T cell uses its CD8 glycoprotein to bind to the MHC-I of an infected host cell.

Place the following steps of phagocytosis in the order that they occur:
1 Endosome fuses with lysozome
2 Dendritic cell engulfs Rhinovirus
3 Epitopes are attached to MHC-II
4 Digestion of the Rhinovirus
5 MHC-II plus the attached epitope move to the outside of the dendritic cell

2 Dendritic cell engulfs Rhinovirus 1 Endosome fuses with lysozome 4 Digestion of the Rhinovirus 3 Epitopes are attached to MHC-II 5 MHC-II plus the attached epitope move to the outside of the dendritic cell

Which pair of molecules do NOT directly interact with one another?
CD4 and MHC-II
BCR and TCR
CD8 and MHC-I
BCR and epitope

BCR and TCR. Both of these molecules interact with epitopes. BCRs interact with epitopes on the whole pathogen. TRCs interact with processed epitopes when presented on MHC-II.

Which of the following is NOT a step that ultimately leads to antibody production?
Differentiation of plasma cells
Activation of helper T cells by dendritic cells
Activation of cytotoxic T cells by helper T cells
Immature B cells conducting surveillance for foreign epitopes

The activation of cytotoxic T cells leads down the path of cell-mediated immunity.

A person who has AIDS contracts rare and often life-threatening infections because their helper T cell count is so low. Which of the following components of the immune response still respond to antigen despite the low helper T cell count?
Activation of cytotoxic T cells
Apoptosis of infected host cells
Clonal selection of B cells
Clonal expansion and antibody production

Clonal selection of B cells. B cells can still bind to antigen, which is the process of clonal selection. However, without a helper T cell, clonal expansion and antibody production will not occur.

Which of the following statements is true?
Innate defenses are enough to keep a person healthly.
Adaptive defenses include humoral immunity only.
Adaptive defenses include both humoral and cellular immunity.
Memory B cells are typically established when the B cell binds to an antigen.

Adaptive defenses include both humoral and cellular immunity

While we usually think of fever as a bad thing, a fever is actually signifying that an immune response is progressing! Overall, which of the following cytokines would be most involved in increasing fever response?

Interleukin-2
Interleukin-4
Interleukin-12
Interleukin-10
Interleukin-1

Interleukin-1. When immune cells sense pathogens, certain components of the pathogen stimulate the innate cells to produce cytokines. When Interleukin-1 is produced, it acts on the hypothalamus to "crank up the heat" and results in fever and increased inflammatory processes. The other cytokines listed have separate functions such as T-cell responses (Interleukin-2), B-cell responses (Interleukin -4), anti-inflammation (Interleukin -10), or cell differentiation (Interleukin -12).

A physician wants to stimulate immunological memory in a patient. Which of the following types of immunity would be the most useful?
naturally acquired passive immunity
naturally acquired active immunity
artificially acquired passive immunity
artificially acquired active immunity

artificially acquired active immunity

A particular molecule has a small molecular mass of approximately 1000 daltons. What should be done to make this molecule more antigenic?
Enzymatically cleave it into smaller pieces.
Bind it to a starch molecule.
Bind it to a large protein.
Nothing; this molecule is already very antigenic.

Bind it to a large protein.

Babies that are fed formula instead of being breastfed partially lack which of the following types of immunity?
naturally acquired active immunity
naturally acquired passive immunity
artificially acquired active immunity
artificially acquired passive immunotherapy

naturally acquired passive immunity

Mutations in RAG will directly cause problems in which of the following processes?
formation of variable region gene combinations
synthesis of antibody molecules
secretion of antibody molecules from a B cell
activation of plasma cells

formation of variable region gene combinations. Without RAG, recombination of BCR variable region genes cannot take place.

IgM is the first class of antibodies to be made during an immune response because ____.
B cells producing IgM develop more rapidly than other types
IgM is a multifunctional class of antibody
the genes for IgM production are the most active ones in a B cell
the gene for the mu Fc region is the first to be attached to the variable region gene

the gene for the mu Fc region is the first to be attached to the variable region gene. Since IgM is produced first during an infection, it fulfills an important role in limiting the infection.

Which of the following is NOT associated with killing by a cytotoxic T cell?
secretory component
granzyme
perforin
CD95

secretory component. Perforin, granzyme, and CD95 all play a role in different types of cytotoxic T cell activity.

The majority of T cells that leave the thymus will have which of the following characteristics?
They recognize autoantigens and do not recognize MHC.
They are able to recognize MHC and do not recognize autoantigens.
They recognize both MHC and autoantigens.
They recognize foreign antigens and do not recognize MHC.

They are able to recognize MHC and do not recognize autoantigens. The majority of T cells that leave the thymus recognize MHC and foreign antigens, but they do not recognize autoantigens.

Which of the following is NOT associated with the processing of an endogenous antigen?
a phagolysosome
a Golgi body
endoplasmic reticulum
MHC class II

a phagolysosome. Fragments of endogenous antigens are complexed with MHC class I molecules in the endoplasmic reticulum. They are then packaged into vesicles by a Golgi body and transported to the cytoplasmic membrane, where they are exposed to the outside. Phagolysosomes are associated with the processing of exogenous antigens.

Which of the following would be UNLIKELY to cause a cell-mediated immune response?
Staphylococcus aureus
Mycobacterium tuberculosis
malignant melanoma
hepatitis B virus

Staphylococcus aureus. Hepatitis B virus, Mycobacterium tuberculosis, and various types of cancers such as malignant melanoma would all be expected to stimulate a cell-mediated immune response. Staphylococcus aureus, like all extracellular bacterial pathogens, would be more likely to stimulate a humoral immune response.

Which of the following classes of antibodies is most likely to be made by the oldest plasma cell in a population of B cells?
IgM
IgG
IgA
None of the listed responses is correct.

IgA. Plasma cells begin by secreting IgM, but can class switch and begin making IgG. If they class switch a second time, they can make IgA or IgE.

Mucous membranes are a part of
innate defense.
humoral immunity.
adaptive defense.
the complement system.
cell-mediated immunity.

innate defense

According to the animation, B cells interact directly with
inflammation.
the complement system.
phagocytes.
helper T cells.

helper T cells.

Which of the following defense systems would be involved in eliminating virally-infected cells?
Humoral immunity
T lymphocytes
Phagocytosis
Complement system

T lymphocytes

According to the animation, antibodies interact with which innate defenses?
First-line defenses
Inflammation
Phagocytosis, inflammation, and the complement system
Phagocytosis and the complement system
Phagocytosis
The complement system

Phagocytosis and the complement system

Which cells directly attack abnormal cells in the body?
Cytotoxic T cells
Phagocytes
B cells
Helper T cells

Cytotoxic T cells

Which part of the adaptive immune response involves B cells?
Humoral
Cell-mediated
Neither humoral nor cell-mediated
Both humoral and cell-mediated

Humoral

Antibodies are a part of which type of immunity?
Humoral
Cell-mediated
Both humoral and cell-mediated
Neither humoral nor cell-mediated

Humoral

Antigen processing and presentation
is the way foreign cells engulf macrophages.
is only accomplished by bacterial cells.
is a way for viruses to infect cells.
is a way for a cell to give information about its activities.

is a way for a cell to give information about its activities.

Why would a body cell that is not a phagocyte need to present antigens?
Antigens are infectious and can spread to normal cells.
All cells of the body can engulf invading cells.
Non-phagocytic body cells can become infected with a virus.
Antigens are required for cell-to-cell attachment.

Non-phagocytic body cells can become infected with a virus.

How do phagocytes communicate to other cells what they have captured?
They spread viruses to other cells.
They present antigens from engulfed foreign cells.
They engulf virally infected cells.

They present antigens from engulfed foreign cells.