Deck 25: Immune Mechanisms

Question 1

Some intracellular pathogens produce phagocyte-killing proteins called ________ that kill the phagocyte after ingestion of the pathogen.

A)antibodies
B)antigens
C)leukocidins
D)pus

Answer 1

C

Question 2

Streptococcus pyogenes produces proteins called ________,which alter(s)the surface of the pathogen and inhibits phagocytosis.

A)glycolipids
B)leukocidins
C)M proteins
D)pus

Answer 2

C

Question 3

The part of the antigen recognized by the antibody or TCR is called the

A)epitope.
B)antigen-binding site.
C)antigenic complex.
D)light chain.

Answer 3

A

Question 4

Which of the following are found on the surfaces of ALL nucleated cells?

A)Class I MHC proteins
B)Class II MHC proteins
C)G proteins
D)M proteins

Question 5

________ is the acquired inability to mount an adaptive immune response against self.

A)Memory
B)Specificity
C)Tolerance
D)Immunogenicity

Question 6

The enhancement of phagocytosis due to deposition of antibody on the surface of a pathogen or antigen is called

A)complementation.
B)opsonization.
C)inflammation.
D)antibody class switching.

Question 7

Oxygen compounds toxic to pathogens include

A)hydrogen peroxide.
B)hypochlorus acid.
C)nitric oxide.
D)hydrogen peroxide,hypochlorus acid,and nitric oxide.

Question 8

Antibody-mediated immunity is particularly effective against

A)extracellular pathogens.
B)intracellular pathogens.
C)both extra- and intracellular pathogens.
D)None of the answers are correct.

Question 9

T cells recognize antigens with their

A)antibodies.
B)leukocidins.
C)M proteins.
D)T cell receptors.

Question 10

A cross-reaction is an interaction between an antibody or TCR and

A)a heterologous antigen.
B)a homologous antigen.
C)either a heterologous or homologous antigen.
D)None of these are correct.

Question 11

Phagocytes have a pathogen-recognition system known as ________ that leads to the recognition,containment,and destruction of a pathogen.

A)collagen
B)fibrin
C)pattern recognition receptors (PRR)
D)pathogen associated molecular pattern (PAMP)

Question 12

________ are cytotoxins produced by Tc cells that cause apoptosis.

A)Perforins
B)Granzymes
C)Phagocytes
D)Macrophages

Question 13

The primary function of a phagocyte is to

A)destroy pathogens.
B)engulf pathogens.
C)evade pathogens.
D)both engulf and destroy pathogens.

Question 14

Effective immunogens generally have a molecular weight of ________ or greater.

A)1,000
B)5,000
C)7,500
D)10,000

Question 15

TH cells express a ________ protein coreceptor.

A)CD4
B)CD8
C)CD12
D)T cell receptin

Question 16

Another name for programmed cell death is

A)necrosis.
B)perforation.
C)apoptosis.
D)cellular degradation.

Question 17

Which of the following is a function of dendritic cells?

A)antigen presentation
B)plaque formation
C)phagocytosis
D)both phagocytosis and plaque formation

Question 18

Which of the following are NOT phagocytes?

A)dendritic cells
B)monocytes
C)neutrophils
D)erythrocytes

Question 19

Intrinsic properties of immunogens include

A)appropriate physical form.
B)molecular size.
C)sufficient molecular complexity.
D)appropriate physical form,molecular size,and molecular complexity.

Question 20

Natural killer cells like Tc cells use ________ and granzymes to kill their targets without prior exposure or contact with the foreign cells.

A)coagulants
B)M protein
C)perforin
D)interferon gamma

Question 21

Which of the following does NOT influence immunogenicity?

A)the routes of administration
B)foreign nature of the immunogen to the host
C)solubility
D)All of these influence immunogenicity.

Question 22

Dimers of IgA are present in

A)breast milk colostrum.
B)saliva.
C)tears.
D)breast milk colostrum,saliva,and tears.

Question 23

In class switching in the secondary antibody response,the most common antibody switch is from

A)IgA to IgD.
B)IgD to IgE.
C)IgM to IgG.
D)None of the answers are correct.

Question 24

The first cell type active in the innate response is usually a(n)

A)phagocyte.
B)erythrocyte.
C)fibroblast.
D)antibody.

Question 25

Which of the following uses its cell wall glycolipids to absorb hydroxyl radicals and superoxide anions?

A)Staphylococcus aureus
B)Streptococcus pyogenes
C)Mycobacterium tuberculosis
D)Escherichia coli

Question 26

Antibodies are found in

A)milk.
B)mucosal secretions.
C)serum.
D)milk,mucosal secretions,and serum.

Question 27

Extremely high or low doses of an immunogen may suppress a specific immune response by stimulating the development of

A)specificity.
B)memory.
C)tolerance.
D)class switching.

Question 28

Which of the following enzymes are NOT secreted by TH1 to activate macrophages?

A)granulocyte-monocyte colony stimulating factor
B)interferon gamma
C)TNF-α
D)fibrin

Question 29

The measurable strength of binding of antibody to antigen is called

A)binding affinity.
B)epitope.
C)tolerance.
D)virulence.

Question 30

Antigen-presenting cells present antigens to

A)B lymphocytes.
B)T lymphocytes.
C)dendritic cells.
D)neutrophils.

Question 31

The most common circulating antibody,comprising about 80% of the serum immunoglobin,is

A)IgA.
B)IgC.
C)IgD.
D)IgG.

Question 32

Substances that induce an immune response are known as

A)immunogens.
B)antigens.
C)immunoglobins.
D)antigen-presenting cells.

Question 33

The increased rate of O₂ uptake by activated phagocytes is called the

A)hypoxemia.
B)pyogenesis.
C)respiratory burst.
D)peroxidase.

Question 34

Plasma cells usually live for about one

A)week.
B)month.
C)year.
D)decade.

Question 35

Organisms such as Streptococcus pyogenes and Staphylococcus aureus that produce leukocidins are called ________ pathogens.

A)pyogenic
B)radical
C)enterotoxigenic
D)hemorrhagic

Question 36

Which of the following is the name of the heavy chain constant domain of an antibody?

A)beta
B)delta
C)zeta
D)rho

Question 37

When dendritic cells ingest antigen,they migrate to the ________,where they present the antigen to T lymphocytes.

A)kidneys
B)lymph nodes
C)thymus
D)spleen

Question 38

Which of the following is a probable lifespan of memory B cells?

A)5 minutes
B)5 hours
C)5 days
D)5 years

Question 39

Antigen exposure is necessary to

A)induce genetic hypermutation in B cells with productive antibody genes.
B)stimulate B cell to differentiate to plasma cell.
C)stimulate B cell to produce soluble antibodies.
D)stimulate B cell differentiation,antibody production,and genetic hypermutation of antibody genes.

Question 40

Which of the following is NOT an immunoglobin?

A)IgA
B)IgC
C)IgD
D)IgG

Question 41

Th2 cells produce a cytokine that promotes growth and activation of other T cells and activates macrophages.

Question 42

Inflammation is the usual outcome of an adaptive immune response but not an innate immune response.

Question 43

The deactivation of NK cells due to binding of NK receptors to MHC I proteins is called

A)promoting.
B)phagocytosis.
C)licensing.
D)neutralization.

Question 44

The presence of neutrophils in higher than normal numbers in the blood or at a site of inflammation indicates an active response to a current infection.

Question 45

A serum containing antigen-specific antibodies is called an

A)antiserum.
B)antitoxin.
C)antiantigen.
D)anticoagulase.

Question 46

Monocytes are circulating precursors of macrophages and dendritic cells.

Question 47

T cell-target cell interactions induce specialized Tc cells to produce ________ that kill virus-infected target cells.

A)perforins
B)granulozymes
C)leukocidins
D)pyogens

Question 48

When is a bacterial cell more likely to be phagocytized?

A)when antibody binds antigen on its surface
B)when compliment binds an antigen-antibody complex
C)when antibody recognizes self antigens
D)after antibody class-switching

Question 49

Which antibodies bind complement?

A)IgA
B)IgB
C)IgM
D)IgC

Question 50

PRRs were FIRST observed in phagocytes in Drosophila (where they are called Toll receptors).

Question 51

Which of the following is associated with mucosa-associated lymph tissue that produces IgA?

A)breast milk
B)red blood cells
C)blood serum
D)small intestine

Question 52

Staphylococcus aureus produces carotenoids that neutralize singlet oxygen and prevent killing.

Question 53

Dead phagocytes make up much of the material of pus.

Question 54

Proteins derived from infecting viruses are taken up and digested in the cytoplasm in a structure called the

A)phagosome.
B)liposome.
C)proteasome.
D)nucleosome.

Question 55

Localized infections by pyogenic bacteria often form boils or abscesses.

Question 56

TC cells express a(n)________ protein co-receptor.

A)CD4
B)CD8
C)IgM
D)IgG

Question 57

A(n)________ is a group of sequentially interacting proteins important in innate and adaptive immunity.

A)complement
B)opsonin
C)inflammation
D)regeneration

Question 58

The antigen that induces an antibody or TCR is called the

A)homologous antigen.
B)heterologous antigen.
C)cross-reactive antigen.
D)immunogenic antigen.

Question 59

Th17 cells are important in the first stages of the adaptive immune response.

Question 60

Bacterial capsules enhance the adherence of phagocytes to bacterial cell walls,thereby promoting phagocytosis.

Question 61

IgE is found in extremely small amounts in serum.

Question 62

TCRs recognize epitopes only after the immunogens have been partially degraded.

Question 63

Briefly describe the effect of deposition of antibody or complement on the surface of a pathogen or antigen in relation to opsonization.

Question 64

In the adaptive immune response,effective immunity cannot be detected for several days after the first contact with the pathogen.

Question 65

CD4 and CD8 proteins are used for in vitro tests as T cell markers to differentiate TH cells from TC cells.

Question 66

Why must the adaptive immune system develop a capacity to discriminate between foreign antigens and host antigens?

Question 67

ALL antigens are immunogens.

Question 68

A high-affinity antibody binds nonspecifically and loosely to antigen.

Question 69

Nonencapsulated strains of Streptococcus pneumoniae are highly virulent.

Question 70

How is immune memory beneficial to a host organism?

Question 71

The inducing antigens that react with an antibody are called heterologous antigens.

Question 72

Haptens CANNOT bind to or induce an immune response but CAN bind to antibodies.

Question 73

Tolerance is the acquired ability to make an adaptive immune response directed to self-antigens.

Question 74

HLAs are responsible for immune-mediated organ transplant rejection.

Question 75

Why are the chances of an immune response in a patient given between 10µg and 1g of an immunogen (drug)higher than a patient given higher than 1g or lower than 10µg of the same drug?

Question 76

T cell receptors on a particular T cell can recognize more than two antigens.

Question 77

Class I MHC proteins are found ONLY on the surface of B lymphocytes,macrophages,and dendritic cells.

Question 78

The antigen-binding site of ALL antibodies form by interactions between the variable domains of the heavy and light chains.

Question 79

Self-reactive T cells are eliminated during the development of tolerance in the immune system.

Question 80

Briefly describe how a phagocyte engulfs and ingests a pathogen.