Toll-like receptors on phagocytes are directly involved in this stage of phagocytosis • Phagosome formation • Phagolysosome formation • Oxygen dependent killing • Attachment • elimination
Which is true about interferons? • Type stimulates cells to produce antiviral proteins • Rabbit interferon can protect human cells from viral infection • Type II includes alpha and beta forms • The antiviral interferons are prophylactic not threapeutic
This complement pathway is stimulated by mannose sugars which are uncommon in human cells but typically found on bacterial cells: • Lectin • Classical • Alternative • properidin
Signs of this process include redness, heat, swelling, and pain • Complement cascade • Inflammation • Phagocytosis • Type I interferon • Type II interferon
Inflammatory cytokines can contribute to all of these processes except: • Blood vessel dilation • Vasoconstriction • Chemotaxis • Pain • Leukocyte extravasation (diapedesis)
A parasite-infected red blood cell could not be eliminated by a t-killer cell because: • The red blood cell lack MHC I receptors • The red blood cell lacks toll-like receptors • The T-killer is class II MHC restricted • The T-killer cell is unable to activate a B-lymphocyte
Which of the following statement is false? • There are less than 400 stem cell genes that code for B-cell receptors • The heavy chain of a B-cell receptor is coded for by V,D,J, and C genes • Kappa and lambda are types of heavy chains • A Lymphocyte can produce more than one class of antibody molecule
This cell can serve as an antigen presenting cell: • Macrophage • Dendritic cells • B-lymphocyte • A and B • All of the above
This class of antibody exits in two forms: serum and secretory • G • M • E • A • D
B-lymphocytes that bind to T-independent antigens • Cannot be stimulated to produce antibody • Must react with T-helpers to produce antibody • Cannot produce memory cells • Only produce IG-G antibody
Diapedesis is the • loss of blood due to hemorrhaging. • production of only red blood cells. • production of white blood cells, red blood cells, and platelets. • plugging of broken vessels to stop bleeding. • migration of white blood cells from the blood out to the tissues.
Which is incorrect about inflammation? • It can last hours to years. B. Pyrogens cause vasodilation and increased capillary permeability. C. Serotonin causes smooth muscle contraction. D. Fever could be beneficial to inhibiting the pathogen. E. Basophils and mast cells release histamine.
Which is incorrect about complement? • Composed of at least 26 blood proteins • Only appear in the blood during a response to a pathogen • Act in a cascade reaction • Involves a classical pathway • Involves an alternate pathway
Juan has influenza and has aches, pains and a fever. His mother, a physician, tells him to take an antipyretic. What is she telling him to take? • An antibiotic, like erythromycin B. An antiviral drug, like Tamiflu C. An antihistamine D. Acetaminophen, like Tylenol, or aspirin E. Herbal tea with honey
The contribution of B cells is mainly in • inflammation. • humoral immunity. • complement activity. • cell mediated immunity. • phagocytosis.
Helper T cells • secrete antibodies. • function in allergic reactions. • directly destroy target cells. • suppress immune reactions. • activate B cells and other T cells.
Class II MHC genes code for • certain secreted complement components. • self receptors recognized by natural killer cells. • all HLA antigens. • receptors located primarily on macrophages, dendritic cells, and B cells. • All of the choices are correct.
The region of each antibody molecule where amino acid composition is very different from one clone of B lymphocytes to another is the • variable region. • joining region. • constant region. • light region. • hinge region.
T cellresponse to T-cell-dependentantigensrequires • typically a protein antigen. • binding of T cell to a Class II MHC receptor on an antigen-presenting cell. • binding of T cell to a site on the antigen. • interleukin-1 activating the T helper cell. • All of the choices are correct.
An example of artificial passive immunity would be • chickenpox infection is followed by lifelong immunity. • chickenpox vaccine triggers extended immunity to chickenpox. • giving a person immune serum globulins to chickenpox virus after exposure to the disease. • a fetus acquiring maternal IgG to the chickenpox virus across the placenta. • None of the choices are correct.
Soluble antigens are detected in this type of test: • cross-reactions • agglutination • precipitation • specificity • sensitivity
A serum titer involves • serially diluting a serum sample. • determining the lowest dilution of serum that produces a visible reaction. • determining the highest dilution of antigen that produces a visible reaction. • the Western blot method. • None of the choices are correct.
Precipitation tests involve all the following except • they rely on formation of visible clumps for detection. • they include the VDRL test for syphilis. • they are often performed in agar gels. • they can be done in a test tube by carefully adding antiserum over antigen solution. • a cloudy or opaque zone developing where antigen and antibody react
When serum proteins are separated by electrophoresis and then antibodies specific for the serum proteins are placed in a parallel trough in order to form reaction arcs for each protein, the test is called • Ouchterlony double diffusion. • Western blot. • immunelectrophoresis • ELISA
Viral hemagglutination testing • uses a red blood cell that naturally reacts with viral antigens. • analyzes patient serum for specific antibodies to a virus. • has hemagglutination if the patient serum lacks virus specific antibodies. • is used to diagnosis viral diseases such as rubella and mononucleosis. • All of the choices are correct.
All of the following characterize the secondary response to an antigen except • a higher titer of antibody is produced than the primary response. • a longer persistence of antibody than with the primary response. • a quicker rate of antibody synthesis than the primary response. • it is mostly IgM antibodies that are produced. • it is also known as the anamnestic response.
Cytotoxic T cells • stimulate B cell proliferation. • lack specificity for a target cell. • secrete granzymes and perforins that damage target cells. • secrete interleukin-2 to stimulate B and T cells. • All of the choices are correct.
Monoclonal antibodies • originate from a single B cell clone. • have a single specificity for antigen. • are secreted by hybridomas. • are used in immunology lab tests and cancer therapy. • All of the choices are correct.
The immunoglobulin class that has a dimer form found in mucus, saliva, colostrum, and other body secretions is • IgA. • IgD. • IgE. • IgG. • IgM.
Which process involves antibodies coating microorganisms in order to facilitate phagocytosis? • Neutralization • Opsonization • Complement fixation • Agglutination • Anamnestic response
Which is incorrect about the Fc region of an antibody? • It determines the antibody's distribution in the body. • It forms the antigen binding sites. • It contains an effector molecule that can bind to cells such as macrophages and mast cells. • It contains an effector molecule that can fix complement. • It determines the class to which the immunoglobulin belongs.
Superantigens are • body tissues that the immune system mistakes as foreign. • cell markers found in some member of a species but not in other members. • bacterial toxins that activate T cells at a 100 times greater rate than other antigens. • those that evoke allergic reactions. • None of the choices are correct.