MLS 413 - Final Exam with verified
answers A+ rated
affinity (antigen-antibody binding) - correct answer ✔✔the initial force of
attraction that exists between Fab site on an antibody molecule and a single
epitope on an antigen
-strength of attraction depends on specificity of antibody for antigen (ex: cross
reacting antigens have lower affinity)
avidity (antigen-antibody binding) - correct answer ✔✔sum of attractive forces
between an antigen and antibody; the strength with which a multivalent antibody
binds a multivalent antigen
precipitation - correct answer ✔✔when a soluble antigen is combined with a
soluble antibody to produce insoluble compounds that are visible
-requires antibody and antigen to have multiple binding sites for one another and
equivalent concentrations
agglutination - correct answer ✔✔visible aggregation of particles resulting from
combination with specific antibodies
-two step process: sensitization and lattice formation
-*sensitization*: antigen and antibody unite through binding of antigenic
determinant sites (fast and reversible)
-*lattice formation*: visble aggregates form as multiple antigen and antibody
molecules bind to create a stable lattice
,-produced by antibodies called *agglutinins*
agglutination inhibition - correct answer ✔✔an agglutination rxn based on
competition between antigen-coated particles and soluble patient antigens for a
limited number of antibody-combining sites
-lack of agglutination is a positive test result
-used to detect hapten antigens (illicit drugs)
precipitation curve - correct answer ✔✔-zone of equivalence
-prozone phenomenon
-postzone phenomenon
immunoturbidemetry - correct answer ✔✔a technique for determining the
concentration of particles in a solution based on the change in abs caused by a
reduction in light intensity that occurs when an incident beam is passed through a
soln in which antigen-antibody complexes are forming
-measurement of ppt reactions
nephelometry - correct answer ✔✔a technique for determining the concentration
of particles in a solution by measuring the light scattered at a particular angle
from the incident beam as it passes through the solution
-measurement of ppt reaction
-sens: 1010 micrograms Ab/mL
radial immunodiffusion (RID) - correct answer ✔✔serological test detecting the
precipitate of Ag:Ab complexes in which antigen is placed into a well and allowed
,to diffuse outward in all directions; precipitate formation will be in a ring, and the
thickness of the ring is proportional to the concentration of antigen
-*end point method*: allows reaction to go to completion, so the square of
diameter is proportional to antigen conc
-*kinetic method*: faster and measurement is taken before rxn is complete
-measurement of ppt reaction
immunofixation electrophoresis - correct answer ✔✔double diffusion technique
where proteins in pt serum are electrophoresed then Ab is applied directly to the
gel. ppt forms where Ag-Ab combination has taken place
-performed to visualize decr/incr production of Ab classes and to differentiated
monoclonal and polyclonal Igs
-variable sensitivity
-measurement of ppt reaction
ouchterlony diffusion - correct answer ✔✔double diffusion technique where wells
are cut into gel and both Ag and Ab diffuse out radially. a line of ppt forms where
Ag and Ab meet in equiv amts
-3 possible patterns
-*identity*: if the Ag are identical they will react with the same Ab and the ppt
line forms a continuous arc
-*nonidentity*: Ag share no identical determinants and will react with different
Abs and two crossed lines are formed
-*partial identity*: Abs react with two similar Ag forming 2 lines and a spur that
points to the similar Ag
, direct agglutination - correct answer ✔✔patient serum is reacted with Ag that is
naturally found on a particle to test for Abs in pt serum
-ex: ABO typing and hemagglutination
-agglutination indicated the presence of pt Ab to a natural Ag
passive (Indirect) agglutination - correct answer ✔✔uses particles that are coated
with Ag that are not normally found on their surfaces. Ag is attached to the carrier
particle and agglutination occurs if pt Ab is present
-ex tests for: rheumatoid factor, Abs to viruses such as rubella, Abs to group A
strept Ag
reverse passive agglutination - correct answer ✔✔Ab is attached to carrier
particle and agglutination occurs if Ag is present in pt sample
-common applications: rapid ID of Ag from infectious agents, detecting soluble Ag
in urine, SF, and serum
IgM agglutination rxn - correct answer ✔✔most efficient Ig with agglutination and
best reacts between 4-27 degrees Celsius
IgG agglutination rxn - correct answer ✔✔often can't bridge the distance between
particles because of their small size so used with enhancement techniques and
agglutinated best at 30-37 degrees celsius
-require use of second Ab, Coombs reagent which attached to Fc portion of IgG
and helps to bridge gap between RBCs so a visible agglutination reaction can
occur
answers A+ rated
affinity (antigen-antibody binding) - correct answer ✔✔the initial force of
attraction that exists between Fab site on an antibody molecule and a single
epitope on an antigen
-strength of attraction depends on specificity of antibody for antigen (ex: cross
reacting antigens have lower affinity)
avidity (antigen-antibody binding) - correct answer ✔✔sum of attractive forces
between an antigen and antibody; the strength with which a multivalent antibody
binds a multivalent antigen
precipitation - correct answer ✔✔when a soluble antigen is combined with a
soluble antibody to produce insoluble compounds that are visible
-requires antibody and antigen to have multiple binding sites for one another and
equivalent concentrations
agglutination - correct answer ✔✔visible aggregation of particles resulting from
combination with specific antibodies
-two step process: sensitization and lattice formation
-*sensitization*: antigen and antibody unite through binding of antigenic
determinant sites (fast and reversible)
-*lattice formation*: visble aggregates form as multiple antigen and antibody
molecules bind to create a stable lattice
,-produced by antibodies called *agglutinins*
agglutination inhibition - correct answer ✔✔an agglutination rxn based on
competition between antigen-coated particles and soluble patient antigens for a
limited number of antibody-combining sites
-lack of agglutination is a positive test result
-used to detect hapten antigens (illicit drugs)
precipitation curve - correct answer ✔✔-zone of equivalence
-prozone phenomenon
-postzone phenomenon
immunoturbidemetry - correct answer ✔✔a technique for determining the
concentration of particles in a solution based on the change in abs caused by a
reduction in light intensity that occurs when an incident beam is passed through a
soln in which antigen-antibody complexes are forming
-measurement of ppt reactions
nephelometry - correct answer ✔✔a technique for determining the concentration
of particles in a solution by measuring the light scattered at a particular angle
from the incident beam as it passes through the solution
-measurement of ppt reaction
-sens: 1010 micrograms Ab/mL
radial immunodiffusion (RID) - correct answer ✔✔serological test detecting the
precipitate of Ag:Ab complexes in which antigen is placed into a well and allowed
,to diffuse outward in all directions; precipitate formation will be in a ring, and the
thickness of the ring is proportional to the concentration of antigen
-*end point method*: allows reaction to go to completion, so the square of
diameter is proportional to antigen conc
-*kinetic method*: faster and measurement is taken before rxn is complete
-measurement of ppt reaction
immunofixation electrophoresis - correct answer ✔✔double diffusion technique
where proteins in pt serum are electrophoresed then Ab is applied directly to the
gel. ppt forms where Ag-Ab combination has taken place
-performed to visualize decr/incr production of Ab classes and to differentiated
monoclonal and polyclonal Igs
-variable sensitivity
-measurement of ppt reaction
ouchterlony diffusion - correct answer ✔✔double diffusion technique where wells
are cut into gel and both Ag and Ab diffuse out radially. a line of ppt forms where
Ag and Ab meet in equiv amts
-3 possible patterns
-*identity*: if the Ag are identical they will react with the same Ab and the ppt
line forms a continuous arc
-*nonidentity*: Ag share no identical determinants and will react with different
Abs and two crossed lines are formed
-*partial identity*: Abs react with two similar Ag forming 2 lines and a spur that
points to the similar Ag
, direct agglutination - correct answer ✔✔patient serum is reacted with Ag that is
naturally found on a particle to test for Abs in pt serum
-ex: ABO typing and hemagglutination
-agglutination indicated the presence of pt Ab to a natural Ag
passive (Indirect) agglutination - correct answer ✔✔uses particles that are coated
with Ag that are not normally found on their surfaces. Ag is attached to the carrier
particle and agglutination occurs if pt Ab is present
-ex tests for: rheumatoid factor, Abs to viruses such as rubella, Abs to group A
strept Ag
reverse passive agglutination - correct answer ✔✔Ab is attached to carrier
particle and agglutination occurs if Ag is present in pt sample
-common applications: rapid ID of Ag from infectious agents, detecting soluble Ag
in urine, SF, and serum
IgM agglutination rxn - correct answer ✔✔most efficient Ig with agglutination and
best reacts between 4-27 degrees Celsius
IgG agglutination rxn - correct answer ✔✔often can't bridge the distance between
particles because of their small size so used with enhancement techniques and
agglutinated best at 30-37 degrees celsius
-require use of second Ab, Coombs reagent which attached to Fc portion of IgG
and helps to bridge gap between RBCs so a visible agglutination reaction can
occur
