The basic principle of radioimmunoassay is A: The radiolabeled antigen reacted with excessive specific antibody B: The radiolabeled antigen reacted with a limited number of specific antibodies C: Radiolabeled antigen and unlabeled antigen reacted competitively with limited amount of specific antibody D: Radiolabeled antigen and unlabeled antigen reacted with excessive specific antibody

PCR is used to detect ( ) A: Antigen B: Antibody C: DNA or RNA D: Complement

The type of blood is decided by ____.() A: The<br/>type of receptor on RBC membrane B: The<br/>type of antigen on RBC membrane C: The<br/>type of antibody on RBC membrane D: The<br/>type of antigen in plasma E: The<br/>type of antibody in plasma

Cross presentation alerts ______ cells by providing ___________. A: TC; exogenous antigen on MHC I B: TC; endogenous antigen on MHC II C: TH; exogenous antigen on MHC I D: TH; endogenous antigen on MHC II

Compared with normal mice, mice immunized with antigens for many times have the larger and heavier spleens because of ( ). A: proliferation of antigen specific T cells B: proliferation of antigen specific B cells C: proliferation of antigen specific T and B cells D: proliferation of antigen non-specific T and B cells

A child stung by a bee experiences respiratory distress within minutes and lapses into unconsciousness. This reaction is probably mediated by() A: IgE antibody B: IgG antibody C: sensitized T cells D: complement E: IgM antibody

名词解释:抗体 (Antibody,Ab)

基因工程抗体（genetic engineering antibody）

重组抗原疫苗（recombinant antigen vaccine）

An antibody is Y-shaped and has __ identical antigen-binding sites, one on each arm of the Y.