Deck 39: Immunology: Animal Defense Systems

Question 1

Which cell type is not a leukocyte?

A) Macrophage
B) T lymphocyte
C) Basophil
D) Mast cell
E) Red blood cell

Answer 1

E

Question 2

The _______ acid in gastric juice is lethal to many pathogens.

A) sulfuric
B) carbolic
C) hydrochloric
D) formic
E) protease

Answer 2

C

Question 3

Which statement about the complement system is false?

A) It consists of 20 different proteins.
B) It is involved in a cascade of reactions.
C) It lyses invading cells.
D) It consists of highly folded membranes that capture pathogens.
E) It interacts with phagocytes.

Answer 3

D

Question 4

A college student taking a 24-hour bus trip is surrounded by people sniffling and sneezing.This is her first exposure to the bacterial pathogen responsible for their "head cold," but she never develops any symptoms.Which is not one of the factors involved in her resistance?

A) Mucus
B) Lysozymes
C) T cells
D) The nonspecific defense provided by her skin
E) Phagocytes

Question 5

Interferons are produced in response to a _______ infection.

A) viral
B) Gram-negative bacterial
C) Gram-positive bacterial
D) yeast
E) spirochete

Question 6

Which cell releases histamines upon damage?

A) Mast cells
B) T cells
C) Macrophages
D) Monocytes
E) Fibroblasts

Question 7

An innate immune response to a pathogen would not include

A) an increase in lysozyme production.
B) inflammation at the site of exposure.
C) increased flow of mucus.
D) phagocytosis of the pathogen.
E) antibody production.

Question 8

Antibodies are made by

A) T cells.
B) mast cells.
C) macrophages.
D) basophils.
E) B cells.

Question 9

Which cell type is not a phagocyte?

A) Dendritic cell
B) T cell
C) Basophil
D) Macrophage
E) Eosinophil

Question 10

Cruise ship passengers find themselves fighting flulike symptoms for the first four or five days of their trip,but eventually they recover.Which is the last defensive component involved in their recovery?

A) Antibodies
B) Lysozymes
C) Phagocytosis
D) The nonspecific defense provided by the skin
E) Mucus

Question 11

Defensins,which are toxic to a wide range of pathogens,are produced by

A) lymph nodes.
B) mucous membranes.
C) bone marrow.
D) mast cells.
E) basophils.

Question 12

Which type of molecule is most likely responsible for fever during inflammation?

A) Histamines
B) Complement proteins
C) Cytokines
D) Lysozyme
E) Defensin

Question 13

Which statement about specific and nonspecific defenses is false?

A) Defense systems involve recognition of self from nonself.
B) Nonspecific defenses typically act more rapidly than specific defenses.
C) Specific defenses are typically the body's first line of defense.
D) The skin is an example of a nonspecific defense.
E) Antibodies are an example of a specific defense.

Question 14

Which type of defense is not provided by complement proteins?

A) Lysing of viruses
B) Activation of the inflammation response
C) Assistance to phagocytes in recognizing microbes
D) Lysing of invading bacteria
E) Lysing of yeast cells

Question 15

An adaptive immune response to a pathogen would include

A) an increase in lysozyme production.
B) inflammation at the site of exposure.
C) increased flow of mucus.
D) recognition of infected cells by T cells.
E) phagocytosis of the pathogen.

Question 16

For every white blood cell in a given volume of human blood,there are about _______ red blood cells.

A) 2
B) 10
C) 50
D) 100
E) 1,000

Question 17

It has been discovered only recently that the plague of Athens (during the Peloponnesian War)was likely caused by

A) smallpox.
B) the malicious spread of cowpox.
C) gangrene.
D) typhoid.
E) HIV.

Question 18

The bacteria and fungi that typically live and reproduce on the skin without causing disease are called

A) microcytes.
B) ectocytes.
C) pathogens.
D) normal flora.
E) normal fauna.

Question 19

Which nonspecific defense is secreted by mast cells?

A) Complement proteins
B) The normal flora
C) Lysozyme
D) Defensins
E) Histamines

Question 20

Which statement about natural killer cells is false?

A) They are a class of lymphocytes.
B) They can distinguish between normal cells and cells that have been infected by viruses.
C) They can bind antibody-tagged cells.
D) They can induce lyses of targeted cells.
E) They are phagocytic.

Question 21

In terms of its speed and effectiveness,the primary immune response is _______ the secondary immune response.

A) slower but more powerful than
B) quicker and more powerful than
C) very similar to
D) slower and less powerful than
E) quicker but less powerful than

Question 22

Each B cell produces antibodies with _______ kind(s)of antigen specificity.

A) 1
B) 2‒4
C) an average of 6
D) more than 20
E) over 1,000

Question 23

Use the following to answer questions :
Refer to the experiment below,which points to blood as an important factor in adaptive immunity.
Which statement about the effects of toxin from bacteria strain B is true?

A) Toxin from bacteria strain B is more lethal than toxin from strain A.
B) Toxin from bacteria strain A is more lethal than toxin from strain B.
C) Injection with a sublethal dose of toxin from bacteria strain B provides more benefit than injection with serum from an unexposed animal.
D) Toxin from bacteria strain B is as lethal as toxin from strain A.
E) The diagram provides insufficient information to reach a conclusion about the effects of toxin from bacteria strain B.

Question 24

The clonal selection of B cells results in

A) changes in antibody shapes to match different antigens.
B) an individual's possessing only one type of B cell.
C) many genetically identical copies of the initial naïve B cell that recognized an antigen.
D) the production by each B cell clone of antibodies with multiple antigen specificities.
E) the selection of B cells that recognize self antigens.

Question 25

Which statement about the humoral immune response is true?

A) It involves B cells directly killing pathogens.
B) It is carried out by T cells.
C) It involves soluble antibodies.
D) It is a nonspecific response.
E) It is induced by histamines.

Question 26

Which statement is true?

A) Plasma cells secrete cytokines.
B) Effector T cells secrete antibodies.
C) Memory B cells can persist in the body for several decades.
D) Macrophages present antigen to B cells.
E) T cells present antigen to B cells.

Question 27

Refer to the diagram below illustrating an immune response to an antigen.The cell labeled A is a _______ cell involved in a(n)_______ immune response.

A) mast;innate
B) B lymphocyte;humoral
C) T lymphocyte;cellular
D) T-helper;adaptive
E) plasma;humoral

Question 28

When a T cell is activated by an antigen,it will most likely

A) secrete antibodies.
B) proliferate.
C) die.
D) become a B cell.
E) become a plasma cell.

Question 29

The diversity among antibodies occurs mainly through

A) posttranslational modifications.
B) protein-folding differences.
C) different patterns of methylation.
D) changes in their DNA.
E) differential expression of genes.

Question 30

Epitopes are

A) molecules produced by mast cells.
B) produced by clonal selection.
C) specific sites on antigens that are recognized by the immune system.
D) responsible for immunological tolerance.
E) antibodies that were first discovered by Jenner.

Question 31

The T-helper cell response is modulated by all of the following except

A) erythrocytes.
B) B cells.
C) macrophages.
D) dendritic cells.
E) antigens.

Question 32

When an individual is first exposed to the smallpox virus,several days pass before significant numbers of specific antibody molecules and T cells are produced.However,a second exposure to the virus causes a large and rapid production of antibodies and T cells.This later response is an example of

A) autoimmunity.
B) phytoalexins.
C) phagocytosis.
D) interferon production.
E) immunological memory.

Question 33

After a T_H cell has bound to an antigen-presenting cell,it releases cytokines that simulate B cells and T_C cells bearing receptors to the same antigen to divide.This is the _______ phase of the humoral and cellular immune responses.

A) activation
B) humoral
C) effector
D) cellular
E) recognition

Question 34

Use the following to answer questions :
Refer to the experiment below,which points to blood as an important factor in adaptive immunity.
Suppose that in the final step of the experiment,all the animals were injected with a lethal dose of toxin from bacteria strain B rather than from strain A.What would be the most likely outcome?

A) Only the animal on the left would die.
B) Only the animal on the right would die.
C) Only the animal in the middle would die.
D) Both the animal on the left and the animal in the middle would die.
E) None of the animals would die.

Question 35

Lymphocytes that are specific for certain antigens proliferate by a process known as

A) effector selection.
B) clonal activation.
C) recognition.
D) monoclonal formation.
E) clonal selection.

Question 36

The removal of immature B and T cells that respond against self antigens is called clonal

A) recombination.
B) deletion.
C) selection.
D) attenuation.
E) inactivation.

Question 37

In autoimmune diseases such as rheumatoid arthritis,damage to tissue occurs when the immune system fails to

A) induce the production of IgE by mast cells.
B) distinguish self tissues from pathogens.
C) induce the production of lysozyme.
D) induce platelet aggregation.
E) recruit macrophages.

Question 38

The extraordinary diversity of antibodies results in part from

A) the action of monoclonal antibodies.
B) the splicing of protein molecules.
C) the action of cytotoxic T cells.
D) the rearrangement of genes.
E) their remarkable nonspecificity.

Question 39

Which action does not occur during inflammation and wound healing?

A) Histamines cause capillaries to constrict.
B) Phagocytes engulf bacteria and other dead cells.
C) Wound healing begins when signaling molecules stimulate endothelial cell division.
D) Some cytokines elevate body temperature.
E) Mast cells release prostaglandins.

Question 40

Which is not a key trait of a primary specific immune response?

A) Ability to respond specifically to a wide diversity of foreign molecules and organisms
B) Rapid response to an infection
C) Generally long-lasting immunological memory
D) The ability to recognize "self" from "nonself"
E) Effective response to a repeat infection

Question 41

Many passengers on a cruise ship at sea are suffering from flulike symptoms.Which component of the immune system will protect the passengers from becoming sick from the same viral strain the next time they are exposed?

A) Antibodies
B) Lysozymes
C) Mucus
D) Complement proteins
E) Defensins

Question 42

One V gene,one D gene,and one J gene encode for the _______ region of the _______ chain of a specific antibody.

A) constant;light
B) constant;heavy
C) specific;light
D) specific;heavy
E) variable;heavy

Question 43

Terminal transferase

A) plays a role in clonal selection.
B) often adds nucleotides to the ends of immunoglobulin gene DNAs.
C) can be used to suppress the immune system during organ transplants.
D) splices the primary RNA transcript to remove transcripts of extra J genes during B cell development.
E) induces gene recombination.

Question 44

The mechanisms of joining and random deletion account for only a part of antibody diversity.Vast numbers of unique immunoglobulins are also produced by

A) mutations.
B) translocations.
C) cell fusion.
D) cell surface proteins.
E) clonal selection.

Question 45

Interactions between macrophages and lymphocytes are coordinated by

A) MHC proteins.
B) T cell receptors.
C) mast cells.
D) platelets.
E) antibodies.

Question 46

A bacterium in the bloodstream is most likely to encounter an _______ antibody.

A) IgE
B) IgM
C) IgG
D) IgD
E) IgA

Question 47

Antigens can bind to an antibody at _______ site(s);binding occurs at the _______ regions of the antibody.

A) one;constant
B) one;variable
C) one;specific
D) two;variable
E) two;constant

Question 48

If you were vaccinated against measles as a child,you still have immunity to the disease decades later because

A) plasma cells secrete cytokines.
B) effector T cells secrete antibodies.
C) memory B cells can persist in the body for several decades.
D) cytotoxic T cells can live for several decades.
E) Both a and b

Question 49

Use the following to answer questions :
Refer to the diagram below showing a receptor on a cell.
What type of cell is shown in the diagram?

A) B lymphocyte
B) T lymphocyte
C) Plasma cell
D) Mast cell
E) Macrophage

Question 50

Which class of antibodies is most likely to trigger a large release of histamines and subsequent inflammation?

A) IgE
B) IgG
C) IgM
D) IgD
E) Monoclonal

Question 51

Which statement about MHC I proteins is true?

A) They are found primarily on immune system cells.
B) They protect a developing fetus from its mother's immune system.
C) They are found on the surface of most mammalian cells.
D) They are antibodies.
E) They activate B cells.

Question 52

Which is not a mechanism that generates antibody diversity in the human immune response?

A) Imprecise recombination of the V,D,and J regions of DNA
B) Insertion of RNA sequences into the DNA coding for antibody production
C) Random placement of extra nucleotides (by means of terminal transferase)on DNA as it is recombined to code for antibodies
D) Spontaneous mutations in immunoglobulin genes
E) DNA recombination events during B cell development

Question 53

Which symptom or observation would support the hypothesis that a person is undergoing an adaptive immune response after exposure to a pathogen?

A) An increase in lysozyme production
B) Inflammation at the hypothesized site of exposure
C) Increased flow of mucus
D) Lysis of infected cells by T cells
E) Phagocytosis of the pathogen

Question 54

The _______ region of an antibody determines its class;the _______ region determines its specificity.

A) constant;specific
B) constant;variable
C) specific;constant
D) specific;variable
E) variable;constant

Question 55

Use the following to answer questions :
Refer to the diagram below showing a receptor on a cell.
Which of the following binds to the region of the receptor indicated by the arrow?

A) Antigen only
B) MHC protein only
C) Antigen‒MHC complex
D) Allergen
E) Antibody

Question 56

Which statement about T cells is true?

A) The T cell receptor is an immunoglobulin.
B) The T cell receptor has two chains.
C) T cell receptors bind to intact antigens.
D) The T cell receptor is secreted.
E) The T cell receptor lacks variable regions.

Question 57

B cells mature in

A) the thymus.
B) lymph nodes.
C) bone marrow.
D) the spleen.
E) circulating blood.

Question 58

Soluble antibodies have all of the following roles except

A) binding to a pathogen to facilitate phagocytosis by macrophages.
B) acting as a B cell antigen receptor.
C) cross-linking pathogens to one another.
D) attracting complement components to pathogens.
E) attracting natural killer cells.

Question 59

The simplest immunoglobulins have _______ polypeptide chain(s).

A) one
B) two
C) three
D) four
E) six

Question 60

The most abundant antibody class circulating in the human body is

A) IgG.
B) IgD.
C) IgM.
D) IgA.
E) IgE.

Question 61

The retrovirus HIV specifically destroys T_H cells and thus disrupts the _______ response(s).

A) humoral immune
B) cellular immune
C) humoral and cellular immune
D) inflammatory
E) autoimmune

Question 62

HIV can be transmitted from person to person by all of the following except

A) blood.
B) semen.
C) vaginal fluid.
D) breast milk.
E) sneezing.

Question 63

The body's tolerance to its own molecules involves all of the following except

A) the deletion of immature B cells that recognize self antigens.
B) the activation of regulatory T cells.
C) the deletion of immature T cells that recognize self antigens.
D) clonal selection.
E) interleukin-10 expression.

Question 64

Which statement about AIDS is false?

A) The chances of getting the disease are increased if an individual already has a sexually transmitted disease.
B) AIDS induces autoimmunity.
C) Most people who die from AIDS do not die because of HIV infection directly,but from other infections that would normally be eliminated by T cells.
D) HIV can be transmitted through the blood of an infected mother to her child.
E) HIV can be transmitted via sexual intercourse.

Question 65

Which is not an opportunistic infection or cancer often associated with AIDS?

A) Kaposi's sarcoma
B) Pneumocystis pneumonia
C) Epstein-Barr virus
D) Lymphoma
E) Breast cancer

Question 66

Which event must take place for a B cell to become an antibody-secreting plasma cell?

A) Activation of the complement system
B) The binding of a T_H cell to an antigen‒MHC class II complex presented by the B cell
C) Clonal deletion of nonreactive B cells
D) Inflammation
E) T_C cell activation

Question 67

Which statement about HIV and AIDS is true?

A) Opportunistic infections as a result of HIV infection are the usual cause of AIDS deaths.
B) HIV causes death directly.
C) AIDS typically arises from HIV infection after a dormancy period of one month.
D) The HIV viral load rises steadily from the initial infection.
E) T_C cells are infected.

Question 68

A successful cellular immune response to a viral infection is dependent upon the activity of

A) cytotoxic T cells.
B) helper T cells.
C) regulatory T cells.
D) dendritic cells.
E) B cells.

Question 69

T cells mature in

A) the thymus.
B) lymph nodes.
C) bone marrow.
D) the spleen.
E) the thoracic duct.

Question 70

Which statement is true?

A) There is little polymorphism at MHC loci in humans.
B) T cell receptors recognize antigenic fragments only when they are bound to an MHC molecule.
C) T_C cell receptors bind directly to antigen.
D) All nucleated cells express class II MHC proteins.
E) T cells recognize antigens presented by the B cell receptor.

Question 71

A T cell is stimulated by the binding of its receptor to an antigen‒MHC complex expressed by a host cell.The outcome of this interaction is the death of the cell if

A) the antigen is presented by a class I MHC protein.
B) the antigen is presented by a class II MHC protein.
C) a mast cell is involved.
D) a B cell is activated.
E) the T cell is a helper T cell.

Question 72

In its initial stages,HIV infection is controlled by

A) macrophages.
B) T_H cells.
C) dendritic cells.
D) mast cells.
E) B cells.

Question 73

The cells targeted by HIV are

A) neurons.
B) platelets.
C) red blood cells.
D) mast cells.
E) T_H cells.

Question 74

Which cell type develops in the thymus?

A) Natural killer cells
B) B cells
C) T cells
D) Basophils
E) Macrophages

Question 75

Which statement about MHC proteins is false?

A) MHC proteins are plasma membrane glycoproteins.
B) The major role of MHC proteins is the presentation of antigens to T cell receptors.
C) Class I MHC proteins are found on the surface of every nucleated cell.
D) Class II MHC molecules are found on the surfaces of T cells.
E) Class II MHC molecules are found on the surfaces of B cells.

Question 76

Which consequence of HIV infection is the primary factor leading to the development of acquired immune deficiency syndrome (AIDS)?

A) Destruction of T_C cells by the HIV infection
B) Antibodies made against HIV-infected cells
C) Free circulation of HIV in blood plasma
D) Activation of T_H cells by the HIV infection
E) Destruction of T_H cells by the HIV infection

Question 77

Which statement is false?

A) MHC proteins often act as nonself antigens in transplants between one individual and another.
B) MHC proteins play an important role in self-tolerance.
C) Developing T cells that fail to recognize the body's own MHC proteins undergo apoptosis in a normally functioning body.
D) In transplants of material from one individual to a genetically identical individual,the material is recognized as self and is not rejected.
E) When a T cell binds an antigen‒MHC complex,it interacts physically only with the antigen.

Question 78

Which disease is not caused by autoimmunity?

A) Systemic lupus erythematosus (SLE)
B) Rheumatoid arthritis
C) Type I diabetes
D) AIDS
E) Hashimoto's thyroiditis

Question 79

Hashimoto's thyroiditis is an autoimmune disease.Which cell type normally prevents the development of this disease?

A) T_C cells
B) T_H cells
C) Tregs
D) B cells
E) Dendritic cells

Question 80

Doctors trying to identify the nature of the immune response to a newly identified pathogen note that every time they isolate the antigen that the immune system is responding to,it is bound to the surface of a cell.This means that the component(s)of the immune system involved could be

A) T cell receptors.
B) macrophages.
C) dendritic cells.
D) MHC proteins.
E) All of the above