Module 4 End of Chapter Questions

Question 1

The quality of test results in an agglutination reaction depends on all of the following except:

Duration of incubation
amount of antigen conjugated to the carrier
avidity of antigen conjugated to the carrier
whether the carrier is artificial or biological

Answer 1

Whether the carrier is artificial or biological

Question 2

Flocculation procedures differ from latex agglutination procedures because

Answer 2

Soluble antigen reacts with antibody

Question 3

In the hemagglutination technique, antihuman globulin is used as an enhancement medium to detect ___ antibodies

Answer 3

IgG

Question 4

The prozone phenomenon can result in a

Answer 4

false-negative reaction

Question 5

The effect of competing antibodies seeking to attach to antigen sites is called

Answer 5

steric hindrance

Question 6

the description of a mixed-field graded agglutination reaction is

Answer 6

Few isolated aggregates; supernatant appears red

Question 7

the description of a 1+ graded agglutination reaction is

Answer 7

A few small aggregates: turbid and reddish supernatant

Question 8

The description of a 2+ graded agglutination reaction is

Answer 8

Medium-sized aggregate; clear supernatant

Question 9

The description of a 4+ graded agglutination reaction is

Answer 9

All erythrocytes are combined into one solid aggregate; clear supernatant

Question 10

the definition of precipitation is

Answer 10

Aggregation of soluble test antigens

Question 11

the definition of agglutination is

Answer 11

Aggregation of particulate test antigens

Question 12

the definition of coagulation is

Answer 12

uses antibodies bound to a particle to enhance visibility of agglutination

Question 13

the definition of flocculation is

Answer 13

Based on the interaction of soluble antigen with antibody, resulting in the formation of a precipitate of fine particles

Question 13

the definition of hemagglutination is

Answer 13

Agglutination of erythrocytes in tests for antibody detection

Question 14

artificial or biological carrier that can be used in an agglutination reaction include:

latex particles
colloidal charcoal
erythrocytes coated with antigen in a constant amount
all of the above

Answer 14

all of the above

Question 15

sensitization:

is the first phase of agglutination
represents the physical attachment of antibody molecules to antigens on the RBC membrane
is an irreversible reaction
both a and b

Answer 15

Both a and b

Question 16

agglutination can be used to enhance reactions by all of the following means except:

decreasing ionic strength of the reaction
centrifugation
increasing the pH of the reaction
using colloids and antihuman globulin

Answer 16

Increasing pH of the reaction

Question 17

A negative latex agglutination reaction would appear as

Answer 17

no aggregates

Question 18

A weak (1+ or 2+) latex agglutination reaction would appear as

Answer 18

tiyn aggregates that are barely visible macroscopically

Question 19

A 3+ latex agglutination reaction would appear as

Answer 19

several large aggregates

Question 20

all of the following statements are correct regarding human pregnancy testing except:

test detect hCG
the hCG is secreted by the trophoblast of the developing embryo
the presence of hCG rapidly increases in urine or serum
The presence of hCG in maternal urine or serum persists throughout pregnancy

Answer 20

the presence of hCG in maternal urine or serum persists throughout pregnancy

Question 21

All of the following statements are correct regarding hCG except:

it helps maintain the corpus lateum
it stimulates production of progesterone
it is detectable within 102 hours after the last expected menstrual period
it reaches peak levels at 2 to 3 months after the last menstrual period

Answer 21

It is detectable within 102 hours after the last expected menstrual period

Question 22

A urine specimen for pregnancy testing ___ be frozen

Answer 22

may

Question 23

Nephelometry measures the light scatter of

Answer 23

macromolecules

Question 24

Nephelometry can be used to assay all of the following except: IgM IgG IgD IgA

Answer 24

IgD

Question 25

Protein can be separated into ___ fractions by use of serum electrophoresis

Answer 25

five

Question 26

immunofixation electrophoresis (IFE) is primarily used in the

Answer 26

detection of monoclonal gammopathy

Question 27

IFE can test

Answer 27

serum urine CSF

Question 28

The primary use of IFE is

Answer 28

characterization of monoclonal immunoglobulins

Question 29

IFE can be used to detect the protein variable of

Answer 29

electrophoretic mobility

Question 30

Most M proteins are

Answer 30

IgG

Question 31

chemiluminescence:

Answer 31

has excellent sensitivity and dynamic range does not require sample radiation

Question 32

The description of competitive immunoassay is

Answer 32

A fixed amount of labeled antigen competes with unlabeled antigen from the patient specimen for a limited number of antibody-binding sites

Question 33

the description of sandwich immunoassay is

Answer 33

A sample antigen binds to antibody fixed onto solid phase; chemiluminescent-labeled antibody binds to the antigen-antibody complex

Question 34

enzyme labels often used in indirect procedures are

Answer 34

alkaline phosphate horseradish peroxidase beta-galactosidase

Question 35

the description of the enzyme immunoassay (EIA) is

Answer 35

uses a nonisotopic label

Question 36

The description of the immunofluorescent technique assay is

Answer 36

uses antibody labeled with fluorescein isothiocyanate (FITC)

Question 37

the description of the direct immunofluorescent assay is

Answer 37

uses conjugated antibody to detect antigen-antibody reactions

Question 38

the description of inhibition immunofluorescent assay is

Answer 38

Antigen is first exposed to unlabeled antibody, then to labeled antibody

Question 39

the description of indirect immunofluorescent assay is

Answer 39

Based on antibodies acting as antigens and reacting with antiimmunoglobulins

Question 40

for an enzyme to be used in an EIA, it must meet all of the following criteria except: high amount of stability extreme specificity prescence in antigen or antibody no alteration by inhibitor with the system

Answer 40

Presence in antigen or antibody

Question 41

A fluorescent substance is one that ___light of one wavelength

Answer 41

Absorbs

Question 42

A fluorescent substance has the dual characteristic of ___ light of another longer wavelength

Answer 42

Emitting

Question 43

Which of the following molecules are detected by the enzyme-linked immunoassay (ELISA) technique? proteins peptides hormones all of the above

Answer 43

All of the above

Question 44

What is the major advantage of enzyme-linked immunoassay (ELISA) compared with other quantification labeling methods?

Answer 44

Detection of an antigen or antibody at a low concentration