MLT 243 Immunology, Unit 2 (1-50) star
2) If you want to make a 4mL of a 1:20 dilution, how much serum would be needed?
0.2mL
3) When a staphylococcal infection is passed between patients due to health-care workers not washing their hands, this represents an example of:
The chain of infection
6) If 0.9mL of saline is added to 0.1mL of serum, what does the 0.9mL represent?
The diluent
16) Your supervisor wants you to design a quantitative precipitation assay for a new diagnostic test. What methods would you adopt?
radial immunodiffusion
25) Radial immunodiffusion combined with electrophoresis best describes what?
rocket immunoelectrophoresis
37) Precipitation reactions involve combination of soluble antibody with:
soluble antigen
20) The radial immunodiffusion test is a method involving:
precipitation
4) When 0.5mL of serum is added to 1.5mL of diluent, what dilution does this represent?
1:4
10) Which series of dilutions would be best in order to make a 1:3000 dilution?
1:5, 1:6, 1:100
1) On a serial dilution with the following tubes set up, 1:2, 1:4, 1:8, 1:16, 1:32, and 1:64, there is no visible agglutination in the 1:64 tube. What is the titer of the antibody?
32
21) An example of a qualitative precipitation procedure is: A)Ouchterlony B)radial immunodiffusion C)rapid plasma reagin D)complement fixation
A)Ouchterlony
7) What is the main part of the federal Occupational Exposure to Bloodborne Pathogens Standard Act?
All employees must practice universal precautions at all times
44) If a Coombs' test is positive, what is true?
Antibody has coated patient red blood cells in vivo.
8) What applies to recapping of needles? A)It can be done carefully as long as gloves are worn. B)A sheath can be placed back on the needle with the other hand. C)Transport needles back to the lab for disposal. D) Never manually recap a needle.
D) Never manually recap a needle.
48) Which antibody class may require the use of an enhancement technique to visualize the reaction?
IgG
31) Which technique is best to determine if two fungal antigens are identical?
Ouchterlony immunodiffusion
36) What would be considered a single diffusion reaction?
RID
24) In the Mancini endpoint method of RID:
The squared diameter is proportional to the concentration of antigen.
5) Use of universal precautions is best explained how?
Treating every specimen in the lab as if it were infectious
12) The strength of binding of one Fab on an immunoglobulin to one epitope on an antigen is referred to as
affinity
29) The initial force of attraction between an antigen and an antibody is called:
affinity
27) When antibody combines with a particulate antigen, this is classified as which type of reaction?
agglutination
38) A serological reaction is set up in which the antigen is bound to a large carrier, the antibody is soluble, and they bind and form an insoluble complex that is detected macroscopically. What type of assay is described?
agglutination
40) The process by which particulate antigens such as cells aggregate to form larger complexes when specific antibody is present is called:
agglutination
9) What should be part of a chemical hygiene plan?
appropriate work practices, engineering controls such as fume hoods, employee training
19) Affinity between individual antigen and antibody molecules depends on several types of bonds, such as ionic bonds, hydrophobic bonds, hydrogen bonds, and van der Waals forces. How is the strength of these attractions characterized?
avidity
35) The force that keeps antigen and antibody together after the initial attraction and which is responsible for stability of the antigen-antibody complex is:
avidity
49) An immunoassay is performed in the following manner to look for an Ag in the patient serum: Patient serum + labeled Ag + known Ab are added together and incubated. Unbound material is washed off. The amount of labeled Ag is then measured. What assay is performed?
competitive EIA
18) In radial immunodiffusion, the diameter of the precipitin ring correlates with the:
concentration of antigen
13) A situation in which antibody is in excess as compared to antigen is called:
prozone
28) In what zones is a false-negative reaction likely?
prozone
30) What might adversely affect an electrophoresis reaction?
decreasing the strength of the current, changing the pH of the buffer, increasing the strength of the current
46) What would be the best test to determine evidence of hemolytic disease of the newborn?
direct antiglobulin testing
50) An ELISA assay was performed on a patient's serum sample. What is the relationship of the amount of enzyme activity to the amount of patient analyte measured?
directly proportional
17) The zone at which antibody and antigen are at optimal concentrations so that they form a large insoluble lattice together is called the:
equivalence zone
41) In performing blood typing using the tube method, if the red cell button is not resuspended properly, what are the most likely results?
false-positive
39) A serological test that uses red blood cells coated with exogenous antigens such as bacterial polysaccharides as a method to detect patient antibodies against that exogenous antigen is called:
hemagglutination
42) When a patient's red blood cells combine with anti-A typing serum to produce a positive result, this reaction is known as:
hemagglutination
23) In an Ouchterlony immunodiffusion procedure, a continuous arc of precipitate is observed between two adjacent wells. This is a reaction of:
identity
33) Electrophoresis followed by diffusion of antibody from wells cut in the gel best describes what?
immunoelectrophoresis
32) The Western blot test used to confirm HIV is an example of what?
immunofixation
11) Information on any potentially toxic substance used in a laboratory test kit would be found in:
material safety data sheet
34) Measurement of light scattered at an angle used to quantitate antigen-antibody complexes best describes:
nephelometry
15) An Ouchterlony immunodiffusion assay is set up and a line of precipitation is seen forming between the antigen and antibody wells. The lines of precipitation formed by two adjacent antigen wells cross each other, forming an X. The reaction described is called:
non-identity
43) When carrier particles are coated with an antigen that is not normally found on them, this is known as:
passive agglutination
47) What would enhance an agglutination reaction?
polyethylene glycol (PEG)
22) A situation in which antigen is in excess as compared to antibody is called:
postzone
14) A serological reaction is set up in which the antigen and antibody are both soluble and form an insoluble complex that is detected macroscopically. What type of assay was described?
precipitation
45) Coombs' reagent is used for what purpose?
to enhance agglutination with IgG coated red blood cells
26) Where does lattice formation occur to the greatest extent?
zone of equivalence