The primary function of a phagocyte is to
A) destroy pathogens.
B) engulf pathogens.
C) evade pathogens.
D) both engulf and destroy pathogens.
2)
... [Show More] Which of the following are NOT phagocytes?
A) dendritic cells
B) monocytes
C) neutrophils
D) erythrocytes
3) Which of the following is a function of dendritic cells?
A) antigen presentation
B) plaque formation
C) phagocytosis
D) both phagocytosis and plaque formation
4) 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)
5) Oxygen compounds toxic to pathogens include
A) hydrogen peroxide.
B) hypochlorus acid.
C) nitric oxide.
D) hydrogen peroxide, hypochlorus acid, and nitric oxide.
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.
7) ________ are cytotoxins produced by Tc cells that cause apoptosis.
A) Perforins
B) Granzymes
C) Phagocytes
D) Macrophages
8) Another name for programmed cell death is
A) necrosis.
B) perforation.
C) apoptosis.
D) cellular degradation.
9) 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
10) 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
11) T cells recognize antigens with their
A) antibodies.
B) leukocidins.
C) M proteins.
D) T cell receptors.
12) 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.
13) ________ is the acquired inability to mount an adaptive immune response against self.
A) Memory
B) Specificity
C) Tolerance
D) Immunogenicity
14) Effective immunogens generally have a molecular weight of ________ or greater.
A) 1,000
B) 5,000
C) 7,500
D) 10,000
15) 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.
16) 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.
17) 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.
18) 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
19) TH cells express a ________ protein coreceptor.
A) CD4
B) CD8
C) CD12
D) T cell receptin
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
21) 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
22) Antibodies are found in
A) milk.
B) mucosal secretions.
C) serum.
D) milk, mucosal secretions, and serum.
23) Which of the following is NOT an immunoglobin?
A) IgA
B) IgC
C) IgD
D) IgG
24) The most common circulating antibody, comprising about 80% of the serum immunoglobin, is
A) IgA.
B) IgC.
C) IgD.
D) IgG.
25) The measurable strength of binding of antibody to antigen is called
A) binding affinity.
B) epitope.
C) tolerance.
D) virulence.
26) Which of the following is the name of the heavy chain constant domain of an antibody?
A) beta
B) delta
C) zeta
D) rho
27) Dimers of IgA are present in
A) breast milk colostrum.
B) saliva.
C) tears.
D) breast milk colostrum, saliva, and tears.
28) 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.
29) Plasma cells usually live for about one
A) week.
B) month.
C) year.
D) decade.
30) 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.
31) The first cell type active in the innate response is usually a(n)
A) phagocyte.
B) erythrocyte.
C) fibroblast.
D) antibody.
32) 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
33) Which of the following is a probable lifespan of memory B cells?
A) 5 minutes
B) 5 hours
C) 5 days
D) 5 years
34) The increased rate of O2 uptake by activated phagocytes is called the
A) hypoxemia.
B) pyogenesis.
C) respiratory burst.
D) peroxidase.
35) 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
36) Organisms such as Streptococcus pyogenes and Staphylococcus aureus that produce leukocidins are called ________ pathogens.
A) pyogenic
B) radical
C) enterotoxigenic
D) hemorrhagic
37) Antigen-presenting cells present antigens to
A) B lymphocytes.
B) T lymphocytes.
C) dendritic cells.
D) neutrophils.
38) Substances that induce an immune response are known as
A) immunogens.
B) antigens.
C) immunoglobins.
D) antigen-presenting cells.
39) 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.
40) 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.
41) A(n) ________ is a group of sequentially interacting proteins important in innate and adaptive immunity.
A) complement
B) opsonin
C) inflammation
D) regeneration
42) The antigen that induces an antibody or TCR is called the
A) homologous antigen.
B) heterologous antigen.
C) cross-reactive antigen.
D) immunogenic antigen.
43) Which antibodies bind complement?
A) IgA
B) IgB
C) IgM
D) IgC
44) 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
45) 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.
46) 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
47) TC cells express a(n) ________ protein co-receptor.
A) CD4
B) CD8
C) IgM
D) IgG
48) 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
49) 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.
50) A serum containing antigen-specific antibodies is called an
A) antiserum.
B) antitoxin.
C) antiantigen.
D) anticoagulase.
True/False Questions
1) 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.
2) Monocytes are circulating precursors of macrophages and dendritic cells.
3) PRRs were FIRST observed in phagocytes in Drosophila (where they are called Toll receptors).
4) Th2 cells produce a cytokine that promotes growth and activation of other T cells and activates macrophages.
5) Th17 cells are important in the first stages of the adaptive immune response.
6) Inflammation is the usual outcome of an adaptive immune response but not an innate immune response.
7) Staphylococcus aureus produces carotenoids that neutralize singlet oxygen and prevent killing.
8) Dead phagocytes make up much of the material of pus.
1
9) Localized infections by pyogenic bacteria often form boils or abscesses.
10) Bacterial capsules enhance the adherence of phagocytes to bacterial cell walls, thereby promoting phagocytosis.
11) Nonencapsulated strains of Streptococcus pneumoniae are highly virulent.
12) The antigen-binding site of ALL antibodies form by interactions between the variable domains of the heavy and light chains.
13) T cell receptors on a particular T cell can recognize more than two antigens.
14) In the adaptive immune response, effective immunity cannot be detected for several days after the first contact with the pathogen.
15) Tolerance is the acquired ability to make an adaptive immune response directed to self-antigens.
16) ALL antigens are immunogens.
17) Haptens CANNOT bind to or induce an immune response but CAN bind to antibodies.
18) A high-affinity antibody binds nonspecifically and loosely to antigen.
19) TCRs recognize epitopes only after the immunogens have been partially degraded.
20) The inducing antigens that react with an antibody are called heterologous antigens.
21) HLAs are responsible for immune-mediated organ transplant rejection.
22) Class I MHC proteins are found ONLY on the surface of B lymphocytes, macrophages, and dendritic cells.
23) Self-reactive T cells are eliminated during the development of tolerance in the immune system.
24) CD4 and CD8 proteins are used for in vitro tests as T cell markers to differentiate TH cells from TC cells.
25) IgE is found in extremely small amounts in serum.
Essay Questions
1) Briefly describe how a phagocyte engulfs and ingests a pathogen.
2) How is immune memory beneficial to a host organism?
3) Why must the adaptive immune system develop a capacity to discriminate between foreign antigens and host antigens?
4) Briefly describe the effect of deposition of antibody or complement on the surface of a pathogen or antigen in relation to opsonization.
5) 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?
6) Briefly describe classical complement activation and cell damage.
7) What are the major antigenic barriers for tissue transplantation from one individual to another?
8) How do NK cells discriminate between normal, healthy cells and virus-infected or tumor cells?
9) Briefly describe how B cells are activated.
10) Why are rabies shots given to domestic animals yearly and not just once in the animal's lifetime? [Show Less]