Chapter 16
What is the purpose of an MHC class I protein? MHC class I proteins bind antibodies. MHC class I proteins display epitopes from endogenous antigen. MHC class I proteins break down endogenous antigen. MHC class I molecules display epitopes from exogenous antigen.
-MHC class I proteins display epitopes from endogenous antigen.
Which of the following function in agglutination? IgA antibodies IgE antibodies IgD antibodies IgG antibodies IgA and IgG antibodies
IgA and IgG antibodies
the most prevalent antibody class in the blood is IgA. IgG. IgD. IgM. IgE.
IgG
If a T cell recognizes MHC in conjunction with autoantigens, it will either __________ or differentiate to become a regulatory T cell. undergo apoptosis differentiate to become a cytotoxic T cell differentiate to become a B cell divide into a repertoire of T cells
undergo apoptosis
Which of the following is NOT true about IgG? It is restricted to effects inside the vascular system. It is the most common antibody class. It stimulates a variety of immune responses. It can help protect an unborn fetus.
It is restricted to effects inside the vascular system.
Based on the animation, T cells recognized the antigen displayed by what protein of the B cell? MHC CD4 Antigen TCR BCR
MHC
T cells recognize epitopes only when they are bound to __________. CD8 molecules MHC antibody other T cells
MHC
Which proteins on the antigen-presenting cell are recognized by the helper T-cell? IL-2 receptors CD8 receptors MHC proteins IL-1 receptors
MHC proteins
Which of the cells listed below can present antigens on Class II MHC proteins? Virus infected epithelial cells Healthy epithelial cells Tumor cells Macrophages
Macrophages
Which of the following cells is included as an antigen-presenting cell? Macrophages Hepatocytes Platelets Red blood cells
Macrophages
Which cells are involved in a secondary response? Memory B cells Memory B cells and plasma cells Plasma cells T cells
Memory B cells and plasma cells
Where are MHC molecules located on a cell? Inside the cell cytoplasm On the surface of the cell In the nucleus They are not associated with any one location on the cell
On the surface of the cell
What is the role of plasma cells in humoral immunity? Plasma cells neutralize toxins. Plasma cells produce antibodies. Plasma cells engulf viruses. Plasma cells are phagocytes. Plasma cells activate the complement system.
PLASMA CELLS PRODUCE ANTIBODIES
According to the animation, antibodies directly interact with which innate defenses? Inflammation The complement system Phagocytosis and the complement system Phagocytosis, inflammation, and the complement system First-line defenses Phagocytosis
Phagocytosis and the complement system
Which organelle is responsible for the degradation of exogenous antigen within an antigen-presenting cell? Ribosome Endoplasmic reticulum Phagolysosome Nucleus
Phagolysosome
What is produced by the process of clonal expansion? Plasma cells, T cells, and memory B cells Plasma cells Memory B cells Plasma cells and memory B cells
Plasma Cells, and memory B cells
Which of the following would be UNLIKELY to cause a cell-mediated immune response? Mycobacterium tuberculosis Staphylococcus aureus hepatitis B virus malignant melanoma
Staphylococcus aureus
In the thymus, T cells randomly generate different __________ with a particular shape. cytotoxins epitopes T cell receptors MHC proteins
T cell receptors
Choose the answer that most accurately describes the role of T helper cells in mounting the antibody response. Select the best answer. T helper cells present antigens to B cells, which is required for their activation. T helper cells aid in the response by killing infected cells while the antibody response mounts. T helper cells secrete IL-2, which is required for clonal expansion of B cells. T helper cells aid the antibody response by binding to the B cell MHCII/protein complex and secreting cytokines like IL-4.
T helper cells aid the antibody response by binding to the B cell MHCII/protein complex and secreting cytokines like IL-4.
Which of the following defense systems would be involved in eliminating virally-infected cells? Humoral immunity Phagocytosis Complement system T lymphocytes
T lymphocytes
Which of the following statements about T lymphocytes is FALSE? T lymphocytes have TCRs that recognize antigen only if it is bound to MHC. T lymphocytes directly attack cells and produce the cell-mediated immune response. T lymphocytes produce antibody molecules. T lymphocytes are called such because they mature in the thymus. There are three types of T lymphocytes.
T lymphocytes produce antibody molecules.
An antigen that is potent enough to activate a B cell on its own is known as T-independent antigens. BCR. antibodies. T-dependent antigens.
T- independent antigens
Which receptor on the helper T-cell recognizes the specific antigen from an antigen-presenting cell? IL-2 Receptors IL-1 Receptors TCR CD4
TCR
Natural killer cells are activated by TH1 cells. TH2 cells. antigen-presenting cells. bacterial cells.
TH1 cells.
According to the animation, for approximately how many days is IgG present in the serum? Fifteen days Five days Ten days Twenty days
Ten days
Which of the following most accurately describes how a pathogenic bacterium might be affected by antibodies? The antibodies may coat the surface of the bacteria (opsonization), allowing for it to be tagged for phagocytosis. The antibodies may stick to multiple bacteria, causing agglutination. The antibodies may block proteins necessary for binding the pathogen to the host. The antibodies may block proteins necessary for binding the pathogen to the host, may opsonize the bacterium, or may agglutinate bacteria.
The antibodies may block proteins necessary for binding the pathogen to the host, may opsonize the bacterium, or may agglutinate bacteria.
A sick child may have influenza or RSV. These virus infections have different treatment options, so the physician requests antibody titer tests. The results are as follows: anti-influenza antibodies are primarily IgM, and anti-RSV antibodies are all IgA and IgG. Which of the following is the most appropriate interpretation? the child has concurrent influenza and RSV infections. the child currently has influenza and has previously been exposed to RSV. the child has a current RSV infection and was previously exposed to influenza. the child has neither influenza nor RSV. the results do not provide sufficient data to draw a conclusion.
The child currently has influenza and has previously been exposed to RSV.
Which organelle assists directly with the presentation of MHC-I antigens? The mitochondria The nucleus The phagosome The Golgi apparatus The endoplasmic reticulum
The endoplasmic reticululm
What is apoptosis? The process of programmed cell death. The receptor on a cytotoxic T-cell that recognizes MHC molecules. A protein molecule that forms a pore in the membranes of infected cells. The proliferation of cytotoxic T-cells.
The process of programmed cell death
Which of the following best characterizes clonal selection? The production of identical B cells producing the same antibody The production of identical T cells producing the same antibody The production of different antigens by the same B cell The production of identical B cells producing different antibodies
The production of identical B cells producing the same antibody
Which of the following are characteristics of an adaptive immune response? Select all that apply. The response is specific. The response is inducible. The response is clonal. The response has memory. Fast-acting.
The response is clonal. The response has memory. The response is inducible. The response is specific.
Which of the following is a characteristic of the third line of defense that makes it significantly different from the second line? The responding cells are a variety of cell types. The initial response is very rapid, beginning in minutes to a couple of hours. The response is effective on a broad range of antigens. The response is specific to a single antigen. The response to a second exposure is similar to the response to a first exposure.
The response is specific to a single antigen.
How is the secondary response different from the primary response in terms of antibody concentration in the blood? The secondary response is slower, but produces more antibodies than the primary response. There is no difference with regard to antibody concentration in the blood. The secondary response is faster and produces more antibodies than the primary response. The secondary response is faster, but does not produce more antibodies than the primary response.
The secondary response is faster and produces more antibodies than the primary response.
The majority of T cells that leave the thymus will have which of the following characteristics? They recognize both MHC and autoantigens. They recognize foreign antigens and do not recognize MHC. They recognize autoantigens and do not recognize MHC. They are able to recognize MHC and do not recognize autoantigens.
They are able to recognize MHC and do not recognize autoantigens.
What is a feature of the small fragments presented by MHC-I proteins? They are small peptides, roughly 8-10 amino acids long. They are large proteins from the host. They are derived from bacteria. They are small fragments of nucleic acids, 8-10 nucleotides in length.
They are small peptides, roughly 8-10 amino acids long.
In reference to clonal deletion, what are the clones? They are the T cells that undergo apoptosis. They are the stem cells from which all T cells are derived. They are the cells of the thymus. They are the offspring or potential offspring of lymphocytes.
They are the offspring or potential offspring of lymphocytes
What is the fate of activated cytotoxic T-cells? They proliferate into a clone of cells specific to the same antigen; some of these cells then differentiate into long-lived memory T-cells, while others mature to attack infected cells. Each activated cytotoxic T-cell proliferates, forming a clone of cells specific to the same antigen. They are destroyed via apoptosis. They can mature and attack infected cells. They are infected by viruses. They can differentiate into long-lived memory T-cells.
They proliferate into a clone of cells specific to the same antigen; some of the cells then differentiate into long-lived memory T cells, while other mature to attack infected cells
IgE antibodies are best described as the trigger for antibody-dependent cellular toxicity (ADCC). the antibodies found in body secretions. a cause of basophil and eosinophil degranulation. the most common type of antibody in the blood during the initial phases of an immune response. those involved in complement activation.
a cause of basophil and eosinophil degranulation
The primary immune response involves a slow rise in the concentration of antibodies, followed by a rapid decline. an immediate increase in the concentration of antibodies, followed by a slow decline. a slow rise in the concentration of antibodies, followed by a gradual decline. an immediate increase in the concentration of antibodies, followed by an immediate and sharp decline.
a slow rise in the concentration of antibodies, followed by a gradual decline
An anamnestic response is the term used to describe the production of antibodies from a plasma cell. another name for secondary response. another name for primary response. the appearance of antibodies in serum.
another name for secondary response
Plasma cells produce (antibody/chemokine/cytotoxic) molecules.
antibody
Secretory IgA antibodies are unique because they are present in lymph nodes. are present in the plasma. are connected with J chains and short polypeptides to form dimers. have unique light chains. are Y-shaped molecules.
are connected with J chains and short polypeptides to form dimers
A physician wants to stimulate immunological memory in a patient. Which of the following types of immunity would be the most useful? artificially acquired active immunity naturally acquired passive immunity naturally acquired active immunity artificially acquired passive immunity
artificially acquired active immunity
Which type of cell directly attacks infected cells? Bacterial cells Cytotoxic T-cells Cancerous cells Helper T-cells
cytotoxic T-cells
What is the result when a dendritic cell phagocytizes a microbe and processes it? suppression of the immune response to the microbe display of epitope-MHC I complexes on the surface of the cell display of microbial fragments with CD8 glycoproteins display of microbial epitope-MHC II complexes on the cell surface activation of the dendritic cell to become a plasma cell
display of microbial epitope-MHC II complexes on the cell surface
Toxins and bacterial parts are considered _____ antigen because they are present outside of the body's cells. epitopes autoantigen exogenous endogenous
exogenous
Thymus cells are specialized to participate in clonal deletion because they have the ability to __________. express all of the body's autoantigens undergo apoptosis recognize MHC proteins and epitopes express MHC proteins
express all of the body's autoantigens
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.
fab region
According to the animation, on what day does IgM first appear? Day one Day fifteen Day five Day ten
five days
Which of the following most accurately describes the characteristics of MHCII molecules in mounting the antibody response? Select the best answer. found on all nucleated cells, present endogenous antigens, activate cytotoxic T cells found on APC, present exogenous antigens, activate T helper cells found on APC, present endogenous antigens, activate T helper cells found on APC, present exogenous antigens, activate cytotoxic T cells
found on APC present exogenous antigens activate T helper cells
Most often, antigens are composed of __________. nucleic acids glycoproteins lipids polysaccharides
glycoproteins
According to the animation, B cells interact directly with the complement system. phagocytes. helper T cells. inflammation.
helper T cells.
The type of immunoglobulin illustrated in the figure is The figure shows an immunoglobulin, which consists of several repetitive parts connected in a star-like structure. IgA. IgM. IgE. IgD. IgG.
igM
Mucous membranes are a part of adaptive defense. the complement system. humoral immunity. cell-mediated immunity. innate defense.
innate defense.
Which of the following cytokines act as a signal between leukocytes? tumor necrosis factors interleukins chemokines interferons growth factors
interleukins
Antigen processing and presentation is only accomplished by bacterial cells. is the way foreign cells engulf macrophages. is a way for a cell to give information about its activities. is a way for viruses to infect cells.
is a way for a cell to give information about its activities
You step on something in the yard resulting in a puncture wound that does not bleed freely. Antigens from any microbes that entered the wound will most likely end up in the lymph nodes of the groin. appendix. lymph nodes of the neck (cervical). spleen. lymph nodes of the armpit (axilla).
lymph nodes of the groin.
Enhanced immune responses to subsequent exposures to an antigen to which the body has already been exposed are known as ________ responses. autoimmune third-degree immune memory primary immune allergic
memory responses.
What type of immunity is produced by the body when a person contracts a disease? artificially acquired active immunity innate immunity naturally acquired passive immunity artificially acquired passive immunity naturally acquired active immunity
naturally acquired active immunity
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 passive immunotherapy artificially acquired active immunity
naturally acquired passive immunity
Why would a body cell that is not a phagocyte need to present antigens? Antigens are required for cell-to-cell attachment. All cells of the body can engulf invading cells. Antigens are infectious and can spread to normal cells. Non-phagocytic body cells can become infected with a virus.
non-phagocytic body cells can become infected with a virus
The antibody function known as (agglutination/neutralization/opsonization) is illustrated in the figure.
opsonization
Class I MHC molecules are essential for recognition of chemokines. presentation of exogenous antigens. recognition of class II MHC. detection of IL-2. presentation of endogenous antigens.
presentation of endogenous antigens.
Class II MHC are found on professional antigen-presenting cells. cytoplasmic membranes of nucleated cells. red blood cells. the skin. muscle cells.
professional antigen-presenting cells.
Apoptosis is the process of __________. multiplying into a clone repertoire programmed cell death differentiating into a regulatory T cell presenting epitope in an MHC protein
programmed cell death
Which of the following does NOT contain MHC II on its surface? red blood cell macrophage dendritic cell lymphocyte
red blood cell
The protozoan that causes malaria is an intracellular parasite of red blood cells (RBCs). An adaptive immune response to this parasite is problematic because red blood cells do not produce MHC and, therefore, do not display the fact that they have been infected by presenting antigen. the parasite damages leukocytes along with RBCs. RBCs never enter lymphoid tissue. complement cannot effectively destroy RBCs. RBCs normally produce cytokines necessary for adaptive immune response, which this infection prevents.
red blood cells do not produce MHC and, therefore, do not display the fact that they have been infected by presenting antigen.
Arrange the following statements in the correct order to describe how an antibody response is generated.
1. Dendritic cells process antigens 2. Dendritic cells present antigens on their surface 3. T helper cells recognize MCH11antigen complexes on dendritic cells 4. Stimulated by IL-4 T helper cells differentiate in to Th2 cells 5.B cells are activated after interacting with Th2 cells 6. B cells differentiate into memory cells and plasma cells
IL-2 is involved in __________ Tc cells. clonal expansion of antigen presentation to clonal deletion of self-stimulation of
self-stimulation of
Match the key terms and concepts of the immune system with their descriptions. (#14)
1. Innate Immunity 2. Humoral Immunity 3. Cellular Immunity 4. Immature B cells 5. Dendritic cells 6. Th cells 7. Memory cells 8. Plasma cells 9. Cytoxic T cells
Order the steps in the clonal expansion of antibodies and the production of antibodies.
1. Using its TCR, the Th cell recognizes the viral epitope displayed by the B cell. 2. Cytokines produced by the Th cell activate the B cell, which divides giving rise to two cell types - memory cells and plasma cells. 3. Plasma cells secrete antibodies that recognize the virus.
When do helper T-cells develop into TH1 or TH2 cells? After proliferation into a clonal population Immediately after the binding of the CD4 receptor Before autostimulation After B cell activation
After proliferation into colonel population
The characteristic of adaptive immunity by which the adaptive immune response acts against one molecular shape and no others is called __________. memory clonality inducibility specificity
specificity
Which cells possess MHC class II proteins? Red blood cells Antigen-presenting cells All white blood cells Nucleated cells
Antigen-presenting cells
TH2 cells produce cytokines that activate cytotoxic T-cells. B cells. macrophages. natural killer cells
B cells
The lymphocytes of adaptive immunity called ________ mature in the red bone marrow. macrophages NK cells T cells B cells dendritic cells
B cells
The white blood cells primarily responsible for adaptive immunity are macrophages and neutrophils. macrophages and eosinophils. B lymphocytes and T lymphocytes. NK lymphocytes and neutrophils. neutrophils and dendritic cells.
B lymphocytes and T lymphocytes
The surface of each B lymphocyte is covered with about 250,000 to 500,000 identical copies of (BCR/MHC/TCR).
BCR
What is the function of the CD8 receptor? Produce IL-2 Produce gamma interferon Bind to MHC molecules Activate cytokines
Bink to MHC molecules
Which event happens first during cytotoxic T-cell activation? Secretion of granzymes and perforin CD8 binds to MHC molecules of infected cells Clonal proliferation Production of IL-2 and gamma-interferon receptors
CD8 binds to MHC molecules of infected cells
What purpose does clonal deletion serve? Clonal deletion ensures that no two T cells are alike. Clonal deletion safeguards against making too many T cells. Clonal deletion destroys T cells with receptors complementary to the body's normal autoantigens. Clonal deletion destroys cancerous T cells.
Clonal deletion destroys T cells with receptors complementary to the body's normal autoantigens.
Which of the following is NOT included in the MALT? lymphoid tissue in the respiratory tract Peyer's patches the spleen the appendix lymphoid tissue in the small intestine
the spleen
Which cells directly attack abnormal cells in the body? Phagocytes Helper T cells Cytotoxic T cells B cells
Cytotoxic T cells
HIV directly infects T-cells. Why is this problematic for cell-mediated immunity? Cytotoxic T-cells begin to attack the virally infected T-cells, reducing the number of T-cells in the body. HIV transforms the T-cells into cancer cells. HIV reprograms these cells to attack the body cells. HIV causes cytokines to be produced at much higher levels, altering the normal function of the immune system.
Cytotoxic T-cells begin to attack the virally infected T-cells, reducing the number of T-cells in the body.
Clonal deletion of developing T lymphocytes takes place in which location(s) in the body? the bone marrow the liver the spleen both the bone marrow and the spleen the thymus
the thymus
According to the animation, on which day does the production of IgG occur in the secondary response? Day two Day ten Day five Day fifteen
Day five
When does MHC-II loading occur? During the fusion of vesicles containing MHC-II proteins with vesicles containing digested pathogens During viral infection After passing through the endoplasmic reticulum During phagocytosis of an invading pathogen
During the fusion of vesicles obtaining MHC-II proteins with vesicles containing digested pathogens
What makes agglutination by antibodies possible? Antibodies can recognize bacteria as well as viruses. Antibodies are produced by plasma cells. Antibodies can inactivate toxins. Each antibody has at least two antigen-binding sites.
Each antibody has at least two antigen-binding sites
How can a sufficient humoral immune response occur if a plasma cell only lives for a few days? Memory B cells can also produce antibodies. T cells can also produce antibodies. Each plasma cell can produce up to 2000 antibodies every second. Each plasma cell can proliferate into more plasma cells.
Each plasma cell can produce up to 2000 Antibodies every second
In which location within the cell are epitopes bound to MHC class I proteins? Cytoplasm Golgi body Nucleus Endoplasmic reticulum
Endoplasmic reticulum
How do phagocytes communicate to other cells what they have captured? They spread viruses to other cells. They engulf virally infected cells. They present antigens from engulfed foreign cells.
they present antigens from engulfed foreign cells
Clonal deletion occurs in the __________. blood bone marrow thymus thyroid
thymus
Which of the following best describes why molecules such as glycoproteins are more effective antigens compared to molecules such as starch? Select the best answer. Since starch is a polymer of glucose (which is used by eukaryotic cells for energy), it is not recognized as foreign. Glycoproteins have greater molecular mass compared to starch; therefore, they will elicit a stronger immune response. In general, proteins stimulate stronger immune responses than carbohydrates such as starch. Glycoproteins contain a variety of shapes and subunits that contribute to the overall complexity of the molecule.
Glycoproteins contain a variety of shapes and subunits that contribute to the overall complexity of the molecule.
Which molecule triggers apoptosis? Granzyme Gamma-interferon Perforin IL-2 MHC
Granzyme
Immune cells that secrete cytokines and activate other immune cells are: Virally infected cells Abnormal body cells Helper T-cells Cytotoxic T-cells Invading pathogenic bacteria
Helper T Cells
How do helper T-cells and cytotoxic T-cells work together? Helper T-cells produce cytotoxic T-cells. Cytotoxic T-cells produce cytokines to activate helper T-cells. Cytotoxic T-cells attack abnormal body cells, while helper T-cells attack virally infected cells. Helper T-cells produce cytokines to activate other cells of the immune system
Helper T-cells produce cytokines to activate other cells of the immune system.
Antibodies are a part of which type of immunity? Cell-mediated Neither humoral nor cell-mediated Humoral Both humoral and cell-mediated
Humoral
Which part of the adaptive immune response involves B cells? Humoral Both humoral and cell-mediated Cell-mediated Neither humoral nor cell-mediated
Humoral