Ch. 21 Immune System

Which of the following is NOT a method by which antibodies work? A) agglutinating and precipitating antigen B) neutralizing antigen C) activating cytokines D) enhancing phagocytosis

C) activating cytokines

The clonal selection of B cells, which substance is responsible for determining which cells will eventually become cloned? A) complement B) interferon C) antigen D) antibody

C) antigen

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

C) antigenic

Which of the following is the correct sequence of events in phagocytosis? A) chemotaxis, ingestion, digestion, adherence, killing B) adherence, digestion, killing, ingestion, chemotaxis C) chemotaxis, adherence, ingestion, digestion, killing D) ingestion, adherence, chemotaxis, digestion, killing

C) chemotaxis, adherence, ingestion, digestion, killing

Helper T cells ____. A) often function to decrease the immune response B) release B7 proteins C) function in the adaptive immune system activation D) bind tightly to target cells and release a lymphotoxin called perforin

C) function in the adaptive immune system activation

Small molecules that bind with self-proteins to produce antigenic substances are called ___. A) reagins B) antibodies C) haptens D) ions

C) haptens

Which of the following cells is the most critical cell in immunity? A) cytotoxic T cell B) APC C) helper T cell D) B cell

C) helper T cell

Interferons _____. A) are routinely used in nasal sprays for the common cold B) act by increasing the rate of cell division C) interfere with viral replication within cells D) are virus-specific, so that an interferon produced against one virus could not protect cells against another virus

C) interfere with viral replication within cells

Monoclonal antibodies are used for the diagnosis of all of the following EXCEPT ___. A) hepatitis B) rabies C) juvenile diabetes D) pregnancy

C) juvenile diabetes

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

C) mainly neutrophil and macrophage migration into inflamed areas

Which of the following does NOT respond to cell-mediated immunity? A) foreign tissue transplants B) some cancer cells C) pathogens in the CNS D) intracellular pathogens that reside within host cells

C) pathogens in the CNS

What is the role of interferon in defense against disease? A) protects cells that have not yet been infected by bacteria B) activates the inflammatory process C) protects cells that have not yet been infected by viruses D) activates the complement mechanism

C) protects cells that have not yet been infected by viruses

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

C) results in the formation of plasma cells

Graft rejection may be caused by ____. A) total body irradiation B) use of immunosuppressive drugs C) using a xenograft D) treatment with antilymphocyte

C) using a xenograft

Major innate mechanism that mediates destruction of foreign substances in the body

Complement

___ cells are the only T lymphocytes that can directly attack and kill other cells.

Cytotoxic T

Which of the statements below does NOT describe antigens? A) Antigens can include proteins, nucleic acids, lipoproteins, glycoproteins, and certain large polysaccharides B) Antigens exhibit immunogenicity and reactivity C) The parts of antigen molecules that initiate immune responses are called epitopes or antigenic determinants D) Antigens only come from microbes

D) Antigens only come from microbes

___ are released by activated T cells and macrophages to mobilize immune cells and attract other leukocytes into the area. A) Perforins B) Interleukin 2 proteins C) Interleukin 1 proteins D) Cytokines

D) Cytokines

Which of the following is TRUE about the number of binding sites per functional antibody unit? A) IgD contains 4 binding sites B) IgG contains 6 binding sites C) IgA contains 6 binding sites D) IgM contains 10 binding sites

D) IgM contains 10 binding sites

Cytotoxic T cells ____. A) function mainly to stimulate the proliferation of other T cell populations B) self-destruct once the antigen has been neutralized C) require the double recognition signal of I MHC plus II MHC on the target cell in order to function D) are the only T cells that can directly attack and kill other cells

D) are the only T cells that can directly attack and kill other cells

Which of the following is characteristic of antibodies? A) incapable of being transferred from one person to another B) three binding sites per antibody monomer C) carbohydrate structure D) composed of heavy and light polypeptide chains

D) composed of heavy and light polypeptide chains

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

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

Toll-like receptors (TLRs) trigger the release of ___ to attract white blood cells to the scene. A) histamine B) complement C) protaglandins D) cytokines

D) cytokines

The antibody molecule is held together by ____ bonds. A) sodium B) hydrogen C) amino acid D) disulfide

D) disulfide

Delayed hypersensitivities _____. A) do not involve T cells B) include anaphylactic shock, a systemic vasodilation that results in inadequate blood delivery C) are mediated by B cells D) include allergic contact dermatitis

D) include allergic contact dermatitis

Immunocompetence ____. A) prevents intercellular communication so that only specific cell types respond to the invader B) requires exposure to an antigen C) occurs in one specific organ of the adaptive immune system D) is the ability of individual cells to recognize a specific antigen by binding to it

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

Innate immune system defenses include ___. A) plasma cells B) B cells C) T cells D) phagocytosis

D) phagocytosis

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

D) replaces injured tissues with connective tissue

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

D) their proliferation is enhanced by interleukins 1 and 2

Which of the following is true of immediate hypersensitivities? A) they are adaptive immune responses to disease organisms B) they include allergic contact dermatitis C) they are also called type IV hypersensitivities D) they involve IgE antibodies and the release of histamine from mast cells and basophils

D) they involve IgE antibodies and the release of histamine from mast cells and basophils

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

D) vasodilation

Which of the following is NOT characteristic of the adaptive immune system? A) It is specific for a given organ. B) It is sytsemic. C) It is antigen-specific. D) It has memory.

A) It is specific for a given organ.

Select the correct statement about complement. A) an adaptive immune mechanism is often involved in directing complement to its target B) complement can be activated through 3 pathways: classical, secondary, and alternate C) complement proteins C1 -C9 act exclusively in the classical pathway D) the membrane attack complex consists of complement proteins C3a-C5

A) an adaptive immune mechanism is often involved in directing complement to its target

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

A) can kill cancer cells before the immune system is activated

Select the correct statement about the function of antibodies. A) complement fixation is the main mechanism by which antibodies provide protection B) neutralization is the process by which antibodies cause invading cells to clump together C) the most potent agglutinating agent is IgG D) Antibodies may directly destroy "invaders"

A) complement fixation is the main mechanism by which antibodies provide protection

Regulatory T cells ____. A) may function in preventing autoimmune reactions B) decrease their activity as antigenic stimulus decreases C) release cytokines that increase the activity of cytotoxic T cells and activated B cells D) are the most thoroughly understood T cells

A) may function in preventing autoimmune reactions

Select the correct statement about antigens. A) one antigen may have many different antigenic determinants and may therefore cause the formation of more than one antibody B) "Self-antigens" is another name for incomplete antigens C) only small antigens exhibit reactivity D) the largest type of antigen is called a hapten

A) one antigen may have many different antigenic determinants and may therefore cause the formation of more than one antibody

Which of the following is associated with passive immunity? A) passage of IgG antibodies from a pregnant mother to her fetus B) booster shot of vaccine C) infusion of weakened viruses D) exposure to an antigen

A) passage of IgG antibodies from a pregnant mother to her fetus

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

A) phagocytes

B cells respond to the initial antigen challenge by ___. A) producing progeny cells that include plasma cells and memory cells B) immediately producing antigen-specific antibodies C) forming of a large number of cells that are unlike the original B cell D) reducing its size

A) producing progeny cells that include plasma cells and memory cells

Fever ____. A) production is regulated by chemicals that reset the body's thermostat to a higher setting B) causes the liver to release large amounts of iron, which seems to inhibit bacterial replication C) decreases the metabolic rate of the body to conserve energy D) is a higher-than-normal body temperature that is always dangerous

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

Which of the following is characteristic of complete antigens? A) reactivity with an antibody B) contain many repeating chemical units C) inhibit production of antibodies D) small molecules

A) reactivity with an antibody

Which of the following is not an autoimmune disease? A) type II diabetes B) systemic lupus erythematosus C) multiple sclerosis D) glomerulonephritis

A) type II diabetes

Present the double activation signal to T cells

APCs

___ is the most common type of immediate hypersensitivity.

Allergy

(T/F) A given pathogen will provoke either a cell-mediated response or an antibody-mediated response but not both.

False

(T/F) A graft from a monkey to a human is an example of an allograft.

False

(T/F) Adaptive immunity is provided only by lymphocytes that secrete antibodies.

False

(T/F) Both T cells and B cells must accomplish double recognition. They must simultaneously recognize self and nonself to be activated.

False

(T/F) Fever is seldom beneficial because it speeds up the cellular metabolic rate and will not allow antigen-antibody reactions to occur.

False

(T/F) Monoclonal antibodies can be specific for several antigenic determinants.

False

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

B) Active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies

Which of the following statements is incorrect or false? A) MHC proteins are the cell's identity markers B) Class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens C) Haptens lack immunogenicity unless attached to protein carriers D) Class 1 MHC molecules are built into the plasma membranes of all body cells

B) Class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens

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

B) Isografts are between identical twins

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

B) Our genes

Which of the following is NOT a mechanism for the development of autoimmune disorders? A) mutation followed by the appearance of membrane proteins not previously present B) a second exposure to an allergen C) exposure of previously "hidden" self-antigens to the adaptive immune system D) cross-selection of antibodies formed against foreign antigens with self-antigens

B) a second exposure to an allergen

Which of the following would be classified as a delayed hypersensitivity reaction? A) anaphylaxis B) allergic contact dermatitis C) cytotoxic hypersensitivity D) immune complex hypersensitivity

B) allergic contact dermatitis

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

B) bone marrow

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

B) chemotaxis

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

B) cytotoxic cells

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

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

____ predominate at the sites of chronic infections. A) basophils B) macrophages C) B cells D) esinophils

B) macrophages

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

B) natural killer cells

Complement proteins and antibodies coat a microorganism and provide binding sites, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed ____. A) diapedesis B) opsonization C) agglutination D) chemotaxis

B) opsonization

Which of the following statements is FALSE? A) It is our genes, not antigens, that determine what specific foreign substances our immune system will be able to recognize and resist. B) The lymphoid organs where lymphocytes become immunocompetent are called primary lymph organs. All other lymphoid organs are referred to as secondary lymphoid organs. C) After becoming immunocompetent, the naive T cells and B cells are exported to the bone marrow where the encounters with antigens occur. D) T cells and B cells become fully immunocompetent when they bind with recognized antigens.

C) After becoming immunocompetent, the naive T cells and B cells are exported to the bone marrow where the encounters with antigens occur.

Which of the following statements regarding NK cells is false? A) NK cells attack cancer cells and virus-infected body cells. B) NK cells attack cells that display abnormal MHC antigens. C) NK cells are a type of neutrophil. D) NK cells are present in the blood, spleen, lymph nodes, and red bone marrow.

C) NK cells are a type of neutrophil.

Select the correct statement about immunodeficiency. A) Hodgkin's disease is a hereditary immunodeficiency found in children B) The most common form of immunodeficiency is graft-versus-host (GVH) disease C) The causative agent in acquired immune deficiency syndrome (AIDS) is a virus that recognizes CD4 proteins D) Severe combined immunodeficiency (SCID) disease is an acquired condition

C) The causative agent in acquired immune deficiency syndrome (AIDS) is a virus that recognizes CD4 proteins

Select the correct statement about the prevention of immune attack on "self" A) Neutrophils capable of binding to self-antigens are chemically inactivated B) The development of tolerance is specific to B cells ONLY C) Tolerance is developed during fetal life D) Tolerance to self is due to the action of foreign antigens that inactivate the immune response to one's own tissues

C) Tolerance is developed during fetal life

A(n) ___ is a cell hybrid formed from the fusion of tumor cells and B lymphocytes.

hybridoma

Harmful or disease-causing microorganisms are called ____.

pathogens

___ is an autoimmune disease that severely impairs renal function.

Glomerulonephritis

Stimulate the proliferation of other lymphocytes

Helper T cells

Protects mucosal barriers

IgA

Along with IgM, this is a B cell receptor

IgD

Involved in allergies

IgE

The antibody that becomes bound to mast cells and basophils and causes the cells to release histamine and other chemicals is ___.

IgE

Main antibody of both primary and secondary immune response

IgG

Activates complement

IgM

Adaptive defense system

Immune response

Third line of defense

Immune response

Second line of defense

Inflammatory response

Innate defense system

Inflammatory response and skin and mucous membranes

First line of defense

Intact skin and mucous membranes

Small proteins secreted by virus-containing cells

Interferon

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

Monoclonal

____ cells can lyse and kill cancer cells and virus-infected body cells before the immune system is activated.

Natural killer

Dampen the activity of both T cells and B cells

Regulatory T cells

___ is a dangerous condition where the cytokines are released unchecked, making the capillaries very leaky and thus depleting blood fluids.

Septic shock or sepsis

(T/F) A transfusion reaction is a subacute hypersensitivity to foreign red blood cells.

True

(T/F) Anaphylactic shock can result from an immediate hypersensitivity where the allergen enters the blood.

True

(T/F) Antigens can be complete or incomplete.

True

(T/F) Cellular ingestion and destruction of particulate matter is called phagocytosis.

True

(T/F) It is our genes, not antigens, that determine what specific foreign substances our immune system will be able to recognize and resist.

True

(T/F) Soluble proteins secreted by plasma cells are called antibodies.

True

(T/F) Somatic recombination by B cells allows each B cell to form its own unique antibody genes.

True

(T/F) Some immunocompetant cells will never be called to service in our lifetime.

True

(T/F) Substances capable of triggering the adaptive immune system and provoking an immune response are called antigens.

True

(T/F) The directional movement of cells in response to chemicals is called chemotaxis.

True

(T/F) The mechanism of the "lethal hit" of cytotoxic T cells and NK cells involves a protein called perforin.

True

(T/F) The respiratory burst produced by some macrophages releases free radicals.

True

_____ are grafts taken from another animal species.

Xenografts

___ refers to a group of at least 20 plasma proteins that normally circulate in an inactive state and are a major mechanism for destroying foreign substances in the body.

complement