Chapter 21

The isotype of antibodies that predominate in secretions such as tears or saliva is _______. A) IgM B) IgE C) IgG D) IgA

IgA

________ is the most abundant antibody isotype found in human plasma.

IgG

A graft of a heart valve from a pig to a human is an example of a(n) _________. A) isograft B) allograft C) autograft D) xenograft

Xenograft

Antibody functions include all of the following except: A) targeting foreign cells so that complement proteins can cause cellular lysis. B) binding and inactivating chemical toxins released by bacteria or other microorganisms. C) linking soluble antigens together so that they fall out of solution. D) cross-linking cell-bound antigens on red blood cells when blood types are properly matched.

cross-linking cell-bound antigens on red blood cells when blood types are properly matched.

The T cells that can directly attack and kill other cells are the: A) helper cells. B) cytotoxic cells. C) plasma cells. D) suppressor cells

cytotoxic cells

Which of the following is NOT a method by which antibodies work? A) enhancing the binding of cytokines such as IL-4 to lymphocytes B) binding and neutralizing antigens such as toxins produced by bacteria. C) linking soluble antigens together so they precipitate out of solution. D) enhancing phagocytosis by binding (fixing) and activating the complement system.

enhancing the binding of cytokines such as IL-4 to lymphocytes

Which of the following is NOT a method by which antibodies work? A) enhancing phagocytosis by binding (fixing) and activating the complement system. B) enhancing the binding of cytokines such as IL-4 to lymphocytes C) linking soluble antigens together so they precipitate out of solution. D) binding and neutralizing antigens such as toxins produced by bacteria.

enhancing the binding of cytokines such as IL-4 to lymphocytes

In the clonal selection of B cells, which substance is responsible for determining which cells will eventually respond and become clones? A) antigenic epitopes B) macrophage activating factors C) antibody isotypes D) MHC molecules

antigenic epitopes

Substances capable of triggering the adaptive immune system and provoking an immune response are called ________. A) interleukins B) antigens C) antibodies D) aglutinins

antigens

Cytotoxic T cells: A) are important for reducing the vigorous proliferation of other T cell populations. B) require the double recognition signal of class I MHC plus class II MHC on the target cell in order to function. C) must be eliminated from the body after they are activated to kill a target organ. D) are important for eliminating cells infected with viruses.

are important for eliminating cells infected with viruses.

Natural killer (NK) cells: A) are cells of the specific adaptive immune system. B) can kill cancer cells before the immune system is activated. C) are also called cytotoxic T cells. D) are a type of phagocyte.

can kill cancer cells before the immune system is activated

The process whereby neutrophils and other white blood cells are attracted to an inflammatory site is called: A) diapedesis. B) margination. C) chemotaxis. D) phagocytosis.

chemotaxis

The process whereby neutrophils and other white blood cells are attracted to an inflammatory site is called: A) phagocytosis. B) chemotaxis. C) margination. D) diapedesis.

chemotaxis

he directional movement of cells in response to chemicals is called __________. A) chemotaxis B) phagocytosis C) opsonization D) leukocytosis

chemotaxis

The primary immune response: A) is another name for immunological memory. B) has a lag period while B cells proliferate and differentiate into plasma cells. C) occurs more rapidly and is stronger than the secondary response. D) occurs when memory cells are stimulated.

has a lag period while B cells proliferate and differentiate into plasma cells.

Antigen-induced activation of T cells requires all of the following EXCEPT: A) antigen processing by an antigen-presenting cells B) previous exposure to that antigen C) histocompatibility between the T cell and the antigen-presenting cell D) a functional receptor for antigen in the T cell membrane

histocompatibility between the T cell and the antigen-presenting cell

Which of the following is NOT an inflammatory mediator? A) Leukotrienes B) Clotting factors C) Albumin D) Histamine

Albumin

B lymphocytes develop immunocompetence in the: A) thymus. B) bone marrow. C) lymph nodes. D) spleen.

Bone Marrow

Select the correct statement about active and passive immunity. A) Immunological memory is established by passive immunization. B) The antibodies utilized in active immunity are acquired from another organism. C) Active and passive humoral immunity are both mechanisms of specific immunity that use antibodies. D) Vaccination is an example of passive immunity.

Active and passive humoral immunity are both mechanisms of specific immunity that use antibodies.

________ are released by activated T cells and macrophages to mobilize immune cells and attract other leukocytes into the area. A) Perforins B) Antibodies C) Pheromones D) Cytokines

Cytokines

Which of the following statements about T cell subpopulations is NOT correct? A) Cytotoxic T cells must recognize class II MHC molecules and a foreign antigen fragment for activation. B) The proliferation of CD4+ and CD8+ T cells requires co-stimulation mediated by interactions of CD28 molecules and B7 molecules. C) Helper T cells provide help for isotype (heavy chain) switching in secondary humoral responses. D) Cytotoxic T cells kill cells that are infected with viruses by producing perforin.

Cytotoxic T cells must recognize class II MHC molecules and a foreign antigen fragment for activation.

Which of the following statements is true for helper T cells: A) Helper T cells directly mediate immediate hypersensitivity reactions. B) Helper T cells are essential for neutrophil diapedesis. C) Helper T cells are required for the efficient production of IgG antibodies. D) Helper T cells bind tightly to tumor cells and release a lymphotoxin called perforin.

Helper T cells are required for the efficient production of IgG antibodies.

Which of the following is correct about phagocytosis? A) Bacteria that are coated with antibodies are protected from phagocytosis. B) A phagolysosome is formed by the fusion of a lysosome with the cell nucleus. C) Ingested bacteria are killed by reactive free radicals such as superoxide anion. D) Interferon-gamma is a potent inhibitor of macrophage phagocytic activity.

Interferon-gamma is a potent inhibitor of macrophage phagocytic activity.

Which statement is NOT true regarding the production and functions of the interferons? A) Different types of interferon are produced by leukocytes, T lymphocytes, and fibroblasts B) Interferons protect neighboring cells that have not yet been infected by viruses C) Genetically-engineered interferons are used to treat viral infections such as hepatitis C D) Interferons activate the complement system

Interferons activate the complement system

Select the correct definition about tissue grafts. A) Xenografts are between individuals of the same species. B) Autografts are between two genetically identical individuals. C) Isografts are between identical twins. D) Allografts are between different species.

Isografts are between identical twins.

Which of the following is not characteristic of the adaptive immune system? A) It is antigen-specific. B) It is formed during early adolescence. C) It manifests memory. D) It is systemic.

It is formed during early adolescence.

Which of the following statements about major histocompatibility complex (MHC) molecules is correct? A) MHC molecules are shed by antigen-presenting cells and function as opsonins. B) MHC molecules contain an antigen-binding groove that binds to peptide fragments found inside the cell. C) Class II MHC molecules are expressed by all cell types except erythrocytes. D) Class I MHC molecules are recognized by CD4+ T cells during T cell activation.

MHC molecules contain an antigen-binding groove that binds to peptide fragments found inside the cell.

________ predominate at the sites of chronic infections. A) Eosinophils B) Macrophages C) B cells D) Basophils

Macrophages

Pure antibody preparations specific for a single antigenic determinant are called ________ antibodies.

Monoclonal

Complement proteins and antibodies coat a microorganism and roughen its surface, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed: A) opsonization. B) agglutination. C) diapedesis. D) chemotaxis.

Osponization

________ determine(s) what specific foreign substances our adaptive immune system will be able to recognize and resist. A) Memory cell production B) Our genes C) The type of antigen D) Enzymes present at the time of the invasion

Our Genes

Which statement is true about T cells? A) Their proliferation is enhanced by interleukins 1 and 2. B) Once activated, they cannot secrete cytokines. C) They usually directly recognize antigens, which then activates a subpopulation of killer cells. D) They will develop into cytotoxic T cells if antigen is complexed with class II MHC proteins.

Their proliferation is enhanced by interleukins 1 and 2.

Tolerance of T lymphocytes for self-antigens is produced in the ________. A) lymph nodes B) thymus C) spleen D) bone marrow

Thymus

Select the correct statement about inflammation. A) Neutrophils vacate an inflamed area to avoid injury and cell death. B) Aspirin and other anti-inflammatory substances act by promoting histamine release. C) Tissue edema occurs due to increased vascular permeability. D) Leukopenia-inducing factors are released by damaged tissues.

Tissue edema occurs due to increased vascular permeability.

Which of the following statements regarding cytokines is correct? A) Tumor necrosis factor (TNF) enhances the inflammatory response and causes fever. B) IL-4 induces eosinophilia and macrophage activation. C) IL-5 is a potent B cell growth factor. D) Interferon-gamma promotes development of Th2 helper T cells needed for IgE production.

Tumor necrosis factor (TNF) enhances the inflammatory response and causes fever.

Humoral immunity is mediated by _________. A) cytokines produced by antigen presenting cells B) cytokines produced by B cells C) antibodies produced by T cells D) antibodies produced by plasma cells

antibodies produced by plasma cells

Immunocompetence: A) requires exposure to an antigen. B) is determined by the lymphoid organ where a lymphocyte first encounters an antigen. C) is the ability of individual cells to recognize a specific antigen by binding to it. D) is acquired during a secondary immune response.

is the ability of individual cells to recognize a specific antigen by binding to it.

Which of the following is a part of the innate second line of defense against microorganisms? A) phagocytes B) cilia C) keratin D) gastric juice

keratin

Phagocyte mobilization involves: A) diapedesis, during which cells line up against the capillary wall. B) monocytes as the most active phagocyte. C) mainly neutrophil and macrophage migration into inflamed areas. D) margination, which is the process of white cell movement through the walls of capillaries into injured tissues.

mainly neutrophil and macrophage migration into inflamed areas.

Pure antibody preparations specific for a single antigenic determinant are called ________ antibodies

monoclonal

Cancer cells and virus-infected body cells can be killed before activation of the adaptive immune system by: A) natural killer cells. B) pinocytosis. C) B lymphocytes. D) T lymphocytes.

natural killer cells.

Which of the following is associated with passive immunity? A) long-term immune protection B) infusion of weakened viruses C) a booster immunization D) passage of IgG antibodies from a pregnant mother to her fetus

passage of IgG antibodies from a pregnant mother to her fetus

The mechanism of the "lethal hit" of cytotoxic T cells involves a protein called __________. A) cytoxan B) perforin C) complement D) interferon

perforin

Which of the following is not a type of T cell? A) helper B) regulatory C) cytotoxic D) phagocytic

phagocytic

________ cells can ingest solid particles, especially those that are opsonized.

phagocytic

Cellular ingestion and destruction of particulate matter is called ___________. A) diapedesis B) phagocytosis C) margination D) chemotaxis

phagocytosis

B cells respond to a primary (initial) antigen challenge with Staphylococcus aureus by: A) inducing other nearby B cells to undergo clonal expansion. B) producing low titers of antigen-specific IgM antibodies. C) producing high titers of IgG antibodies D) producing memory cells that will help fight infections by other agents such as Epstein-Barr virus.

producing low titers of antigen-specific IgM antibodies.

Fever: A) production is regulated by chemicals that reset the body's thermostat to a higher setting. B) is dangerous because it reduces antibody production. C) causes the liver to release large amounts of iron, which seems to inhibit bacterial replication. D) decreases the metabolic rate of the body to conserve energy.

production is regulated by chemicals that reset the body's thermostat to a higher setting.

Which of the following is not a function of the inflammatory response? A) sets the stage for repair processes B) prevents the spread of the injurious agent to nearby tissue C) disposes of cellular debris and pathogens D) replaces injured tissues with adipose tissue

replaces injured tissues with adipose tissue

Clonal selection of B cells: A) occurs during fetal development B) results in the formation of plasma cells C) only occurs in the secondary immune response D) cannot occur in the presence of antigens

results in the formation of plasma cells

Graft rejection may be caused by: A) transplanting a hepatic allograft. B) using a high dose of an immunosuppressive drug. C) transplanting a skin autograft. D) transplanting a kidney from an identical twin.

transplanting a hepatic allograft.

The redness and heat of an inflamed area are due to a local hyperemia caused by: A) vasodilation. B) production and release of interferon. C) vasoconstriction. D) phagocyte mobilization.

vasodilation.

A ________ is a graft taken from another animal species.

xenograft