Immune System
Which of the following is correct for isoantigens?

They are antigens found in some members of different species
They are antigens found in all members of a species
They are antigens found in some members of a species
They are antigens found in all members of different species

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Immune System
The role of the M cell is to

they use their cilia to propel mucus out of the small intestine
trap virus in mucus and prevent entry
pass bacteria or virus to underlying macrophages for processing and presentation of antigen
induce apoptosis in virus-infected small intestinal epithelia cells

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Immune System
Which of the following is correct for CD8 T cells?

CD8 T cell receptor recognizes epitopes that are also commonly recognized by B cells
CD8 T cells can kill individual virus-infected cells in a contact dependent fashion
CD8 T cells only recognize virus-infected cells
In the thymus, CD8 T cells undergo positive selection only, whereas CD4 T cells undergo negative selection only

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Immune System
Which of the following statements is false regarding B cells?

B one marrow stem cells migrate to the thymus and develop into B cells
B cells can undergo class switching and produce a different antibody type
B cells that recognize high concentrations of antigens (self) in the absence of other signals undergo apoptosis in the bone marrow
B cells synthesize antibodies and put them on their cell surface

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Immune System
Numerous antibodies can be prepared, against one antigen, each binds to unique epitopes. How is this antibody diversity generated?

Both (a) and (b)
Antibody proteins can physically change their shape to bind different epitopes
By the combination of different heavy and light chains that form the antigen binding site
By rearrangements of the DNA encoding the variable regions of the heavy and light chains

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