Negative selection is characterized by (Select all that apply)
A: the destruction of autoreactive lymphocytes.
B : the ability of these mature lymphocytes to patrol and defend the body against pathogens.
C : repeated mitotic divisions.
D : the elimination
A: the destruction of autoreactive lymphocytes.
D : the elimination of non-functional lymphocytes.
Of the following choices, which represents a change associated with T cell activation? (Select all that apply)
A : promotion of T cell retention
B : transient production of IL-2
C : T cell secretion of cytokines to promote APC effector functions
D : migra
A : promotion of T cell retention
B : transient production of IL-2
C : T cell secretion of cytokines to promote APC effector functions
D : migration of T cells to peripheral sites of injury and infection
During clonal deletion, most autoreactive and immature T and B lymphocytes are eliminated by _____________.
A: phagocytosis
B: complement
C: differentiation
D: apoptosis
D: apoptosis
Antigen processing in the cytosol is associated with class _________ MHC molecules.
A: III
B: II
C: I
D: None of these choices is correct.
C: I
The binding of this cell type with host cells mediates the release of enzymes and triggers apoptosis of the impaired cell.
A: NK cells
B: CD8+ cells
C: TR cells
D: CD4+ cells
B: CD8+ cells
Select the CORRECT statement.
A: most helper T cells possess CD4
B: CD4 binds to NKT cells
C: helper T cells comprise 50% of the T cell population
D: CD4 binds to TCR and class II MHC molecules
D: CD4 binds to TCR and class II MHC molecules
How many classes of MHC molecules participate in various immune functions?
A: There are 4 classes.
B: There are 2 classes but one class is divided.
C: There are 5 classes.
D: There are 3 classes.
D: There are 3 classes.
Antigen processing in phagosomes is associated with class _____________ MHC molecules.
A: II
B: I
C: III
D: I and II
A: II
The T cell receptor includes (Select all that apply)
A : Ig? chains
B : Ig? chains
C : TCR
D : CD3
C : TCR
D : CD3
The outcome of all three complement pathways is
A: pathogen inactivation.
B: increased production of cytotoxic T cells.
C: increased production of B cells.
D: pathogen lysis.
D: pathogen lysis.
Positive selection is characterized by
A: repeated mitotic divisions.
B: the destruction of autoreactive lymphocytes.
C: the ability of these mature lymphocytes to patrol and defend the body against pathogens.
D: the elimination of non-functional lymphocy
C: the ability of these mature lymphocytes to patrol and defend the body against pathogens.
Antigen-presenting cells (APCs) are most commonly
A: B cells, dendritic cells and basophils.
B: B cells, neutrophils and eosinophils.
C: B cells, macrophages and neutrophils.
D: B cells, macrophages and dendritic cells.
D: B cells, macrophages and dendritic cells.
The binding of epitopes to a genetically preprogrammed lymphocyte receptor triggers the proliferation of pathogen-specific T and B ___________ and memory cells.
A: neutrophils
B: eosinophils
C: baseophils
D: lymphocytes
D: lymphocytes
When _______ binds to basophils, histamine is released resulting in changes to the respiratory and circulatory systems.
A: IgE
B: IgA
C: IgM
D: IgG
A: IgE
The B cell receptor includes (Select all that apply)
A : TCR
B : surface IgM or IgD antibody
C : Ig? chains
D : Ig? chains
B : surface IgM or IgD antibody
C : Ig? chains
D : Ig? chains
Antigen-processing pathways correlate with what cellular feature?
A: location of MHC Class I molecule
B: location of foreign protein
C: location of neoantigen
D: location of MHC Class II molecule
B: location of foreign protein
In any given antibody molecule, where does antigen binding occur?
A: hinge region
B: Fab
C: intersection of the "Y"
D: disulfide bridges
B: Fab
Determine which of the following statements is true.
1. ?The classical complement athway typically requires antigen-antibody complexes for activation.
2. The alternative pathway can be activated by C3 hydrolysis, foreign material, pathogens, or damaged ce
D: 1, 2, 3 and 4
While T cells work to eliminate intracellular pathogens, B cells work to eliminate
A: viruses and intracellular parasites.
B: infected cells.
C: extracellular pathogens.
D: cancer cells and transplant tissue.
C: extracellular pathogens.
CD4 associates with the TCR on most other T cells and allows interaction with engulfed, processed antigens presented by class II MHC molecules found on B cells, dendritic cells, and macrophages.
A: True
B:False
A: True