Q&A Hero

Q: Which of the following cytokines acts to stimulate natural killer cells and induce nave T cells to differentiate to TH1 cells?A) IL-1B) IL-6C) IL-12D) TNF-

Q: Which of the following stimulate macrophage differentiation and activation? A) granulocyte-monocyte colony stimulating factor B) interferon gamma C) tumor necrosis factor-alpha D) granulocyte-monocyte colony stimulating factor, interferon gamma, and tumor necrosis factor-alpha

Q: Which of the following are soluble mediators and activators for T lymphocytes and B cells? A) IL-2 B) IL-4 C) IL-5 D) IL-2, IL-4, and IL-5

Q: Chemokines are a group of small proteins that A) attract T cells to sites of injury. B) function as chemoattractants for phagocytes and lymphocytes. C) potentiate specific immune responses. D) attract T cells, phagocytes, and lymphocytes, as well as potentiate specific immune responses.

Q: Communication between cells of the immune system is accomplished in many cases through A) allelic exclusion. B) clonal deletion. C) cytokines. D) allelic exclusion, clonal deletion, and cytokines.

Q: The complete second signal for B cell activation requires which of the following interactions? A) CD40-CK40L interaction B) cytokine-cytokine receptor interaction C) TH-B cell interaction D) All of these are necessary.

Q: Which of the following roles do B cells play? A) antigen presentation B) antigen processing C) antigen uptake D) antigen presentation, processing, and uptake

Q: Which of the following is involved in B cell selection and tolerance? A) clonal anergy B) clonal deletion C) clonal anergy and deletion D) allelic exclusion

Q: More than ________ % of all T cell precursors that enter the thymus do NOT survive the selection process. A) 15 B) 25 C) 45 D) 95

Q: The two-stage thymic selection process for selecting self-tolerant, antigen-reactive T cells results in A) allelic exclusion. B) clonal deletion. C) complementarity-determining regions. D) somatic hypermutation.

Q: Somatic hypermutation occurs only in the ________ regions of rearranged heavy and light chains. A) D B) HV C) J D) V

Q: Assuming that each heavy and light chain has an equal chance to be expressed in each cell, approximately how many possible antibodies can be expressed? A) 192 B) 1,920 C) 19,200 D) 1,920,000

Q: Which of the following contribute to the limitless diversity generated from a relatively fixed number of immunoglobulin genes? A) hypermutation B) random heavy and light chain reassortment C) somatic recombination D) hypermutation, random heavy and light chain reassortment, and somatic recombination.

Q: Clonal anergy is a state of A) antibody production. B) high energy. C) unresponsiveness. D) high energy and antibody production.

Q: An epitope is ________ amino acids long. A) 3-5 B) 10-15 C) 50-60 D) 700

Q: Each of the V domains in immunoglobulins has ________ complementarity-determining regions. A) one B) two C) three D) four

Q: Antibodies consist of four polypeptides, ________ heavy chains, and ________ light chains. A) one / three B) two / two C) three / one D) four / four

Q: An individual usually expresses ________ structurally distinct allele(s) that encode class I MHC proteins. A) one B) two C) four D) six

Q: Which of the following is/are MHC class I genes? A) HLA-A B) HLA-B C) HLA-C D) HLA-A, HLA-B, and HLA-C

Q: Class II MHC proteins have grooves with A) closed ends. B) open ends. C) both open and closed ends. D) neither open nor closed ends.

Q: TCRs associate with the adapter molecule A) CD3. B) CD28. C) Igα. D) Igβ.

Q: The main bonds present in the C domain of antigen-binding proteins are A) hydrogen bonds. B) intrachain disulfide bonds. C) ionic bonds. D) van der Waals forces.

Q: The C domain of antigen-binding proteins functions to A) attach the antigen-binding domain to the cytoplasmic membrane. B) bind to the cytoplasmic membrane of foreign cells. C) complex multiple antigen-binding proteins together. D) bind to epitopes.

Q: Which of the following are proteins that interact directly with antigens during the adaptive immune response? A) immunoglobins B) major histocompatibility complex C) T cell receptors D) all of these

Q: Interaction of a pathogen-associated molecular pattern (PAMP) with a pattern recognition receptor (PRR) results in A) formation of transmembrane pores that cause cell lysis. B) transmembrane signal transduction that initiates transcription of genes involved in phagocytosis, inflammation, and pathogen killing. C) molecular activation of the adaptive immune system. D) a superantigen reaction that can cause septic shock.

Q: Which of the following biomolecules interact with toll-like receptors (TLRs)? A) bacterial LPS B) immunoglobulins C) major histocompatibility complex proteins D) none of these

Q: Pattern recognition receptors (PRRs) are found on which of the following cells? A) macrophages B) bacteria C) neutrophils D) macrophages and neutrophils

Q: C-reactive protein is a A) pathogen-associated molecular pattern (PAMP). B) homotrimeric adaptor protein. C) lipoprotein. D) pattern recognition receptor (PRR).

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

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

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

Q: Monocytes are circulating precursors of macrophages and dendritic cells.

Q: 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.

Q: A serum containing antigen-specific antibodies is called an A) antiserum. B) antitoxin. C) antiantigen. D) anticoagulase.

Q: 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.

Q: 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

Q: TC cells express a(n) ________ protein co-receptor. A) CD4 B) CD8 C) IgM D) IgG

Q: 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

Q: 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.

Q: 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

Q: Which antibodies bind complement? A) IgA B) IgB C) IgM D) IgC

Q: The antigen that induces an antibody or TCR is called the A) homologous antigen. B) heterologous antigen. C) cross-reactive antigen. D) immunogenic antigen.

Q: A(n) ________ is a group of sequentially interacting proteins important in innate and adaptive immunity. A) complement B) opsonin C) inflammation D) regeneration

Q: 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.

Q: 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.

Q: Substances that induce an immune response are known as A) immunogens. B) antigens. C) immunoglobins. D) antigen-presenting cells.

Q: Antigen-presenting cells present antigens to A) B lymphocytes. B) T lymphocytes. C) dendritic cells. D) neutrophils.

Q: Organisms such as Streptococcus pyogenes and Staphylococcus aureus that produce leukocidins are called ________ pathogens. A) pyogenic B) radical C) enterotoxigenic D) hemorrhagic

Q: 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

Q: The increased rate of O2 uptake by activated phagocytes is called the A) hypoxemia. B) pyogenesis. C) respiratory burst. D) peroxidase.

Q: Which of the following is a probable lifespan of memory B cells? A) 5 minutes B) 5 hours C) 5 days D) 5 years

Q: 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

Q: The first cell type active in the innate response is usually a(n) A) phagocyte. B) erythrocyte. C) fibroblast. D) antibody.

Q: 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.

Q: Plasma cells usually live for about one A) week. B) month. C) year. D) decade.

Q: 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.

Q: Dimers of IgA are present in A) breast milk colostrum. B) saliva. C) tears. D) breast milk colostrum, saliva, and tears.

Q: Which of the following is the name of the heavy chain constant domain of an antibody? A) beta B) delta C) zeta D) rho

Q: The measurable strength of binding of antibody to antigen is called A) binding affinity. B) epitope. C) tolerance. D) virulence.

Q: The most common circulating antibody, comprising about 80% of the serum immunoglobin, is A) IgA. B) IgC. C) IgD. D) IgG.

Q: Which of the following is NOT an immunoglobin? A) IgA B) IgC C) IgD D) IgG

Q: Antibodies are found in A) milk. B) mucosal secretions. C) serum. D) milk, mucosal secretions, and serum.

Q: Which of the following enzymes are NOT secreted by TH1 to activate macrophages?A) granulocyte-monocyte colony stimulating factorB) interferon gammaC) TNF-D) fibrin

Q: 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

Q: TH cells express a ________ protein coreceptor. A) CD4 B) CD8 C) CD12 D) T cell receptin

Q: 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

Q: 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.

Q: 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.

Q: 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.

Q: Effective immunogens generally have a molecular weight of ________ or greater. A) 1,000 B) 5,000 C) 7,500 D) 10,000

Q: ________ is the acquired inability to mount an adaptive immune response against self. A) Memory B) Specificity C) Tolerance D) Immunogenicity

Q: 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.

Q: T cells recognize antigens with their A) antibodies. B) leukocidins. C) M proteins. D) T cell receptors.

Q: 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

Q: 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

Q: Another name for programmed cell death is A) necrosis. B) perforation. C) apoptosis. D) cellular degradation.

Q: ________ are cytotoxins produced by Tc cells that cause apoptosis. A) Perforins B) Granzymes C) Phagocytes D) Macrophages

Q: 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.

Q: Oxygen compounds toxic to pathogens include A) hydrogen peroxide. B) hypochlorus acid. C) nitric oxide. D) hydrogen peroxide, hypochlorus acid, and nitric oxide.

Q: 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)