Term
| Which portion of an antibody recognizes antigens? |
|
Definition
|
|
Term
| Heavy chain binds to the light chain portions of the antibody via _____ bonds. |
|
Definition
|
|
Term
| What do the Fab sections of the antibody directly bind to? |
|
Definition
|
|
Term
| True or False: One Ab can bind to one Ag. |
|
Definition
| -FALSE, one Ab can bind 2 separate Ag's |
|
|
Term
| What gives antibodies flexibility? Why is this important? |
|
Definition
-a hinge region
-it (in conjunction with the presence of two arms) allows for binding to two antigens at a time |
|
|
Term
| Because they can bind and cross-link two separate Ag molecules, Ab are referred to as ___________. |
|
Definition
|
|
Term
| How can we quantitate immunoglobulin concentration in Serum? |
|
Definition
-we add antigen to serum containing antibodies
-if it precipitates, then antibodies are present |
|
|
Term
| If sufficient soluble protein molecules can be cross-linked by Ab, the Ag/Ab complex will cout out of solution and (agglutinate/precipitate). Insoluble particulate Ag such as bacteria can be clumped together by Ab in a process called (agglutination/precipitation). |
|
Definition
-precipitate
-agglutination |
|
|
Term
| Definition: Equivalence point/zone |
|
Definition
-where you have the maximum ratio from Ag to Ab
-occurs b/c Ab's will share Ag's, thus making a matrix in soln |
|
|
Term
| What occurs in soln when there is Ab in excess? |
|
Definition
| -no precipitation b/c not enough Ag to go around b/n Ab |
|
|
Term
| What occurs in soln when Ag is in excess? |
|
Definition
| -there is so much Ag that the Ab's do not need to share to create the precipitate matrix |
|
|
Term
| If the soln has precipitated and you add more antigen to it, and mix well, the precipitate may start to re-dissolve. What would cause this to happen? |
|
Definition
| -it will re-dissolve b/c they don't have to share any more, this illustrates that the Ag-Ab bonds are NOT permanent, and thus NOT covalent |
|
|
Term
| Definition: Immunodiffusion test |
|
Definition
-Ag and Ab in agarose gel well and allowed to diffuse towards each other and look for precipitation of Ag:Ab complexes in the agarose gel
-a precipitation line will form at the equivalence point |
|
|
Term
| Can agglutination occur with viruses? Why or why not? |
|
Definition
|
|
Term
| Definition: Slide Agglutination Test |
|
Definition
| -test is performed on a microscopic slide, a drop of inactivated bacteria is mixed with a drop of serum from an animal and is mixed, then observed for agglutination |
|
|
Term
| Definition: Passive Agglutination |
|
Definition
| -agglutination is more sensitive than precipitation, soluble Ag that do not normally agglutinate are sometimes chemically attached to an inert particle: latex beads, RBC |
|
|
Term
| Definition: Latex agglutination test |
|
Definition
| -when Ab are added to the coated particles, they will link the Ag on the particles and agglutinate them |
|
|
Term
| Definition: Passive Hemagglutination Test |
|
Definition
| -When Ab are added to the coated particles, they will link the Ag on RBC's |
|
|
Term
| What are the two important structures that allow Ab to precipitate/agglutinated AG? |
|
Definition
-two arms with IDENTICAL antigen binding sites: Ab are referred to as DIVALENT MOLECULES
-the presence of a HINGE REGION on the Ab molecule gives it great flexibility in binding Ag |
|
|
