Deck 10: Serologic Diagnosis of Infectious Diseases

Question 1

Antibodies that function by attaching to the surface of pathogens and making the pathogens more amenable to ingestion by phagocytic cells are called

A)opsonizing antibodies.
B)neutralizing antibodies.
C)complement-fixing antibodies.
D)chemotaxic antibodies.

Answer 1

A
Antibodies function in different ways. Opsonizing antibodies attach to the surface of pathogens to make them easily ingested by phagocytic cells.

Question 2

Elevations of this antibody may indicate a parasitic infection.

A)IgG
B)IgA
C)IgM
D)IgE

Answer 2

D
Each of the five different classes of antibody has its distinctive molecular configuration and is involved in the immune reaction in a different way. IgE is usually associated with various parasitic infections.

Question 3

For accurate diagnostic of current infection, acute and convalescent sera should reflect a/an

A)decrease in the patient's antibody titer of two doubling dilutions.
B)increase in the patient's titer of two doubling dilutions.
C)decrease in the patient's antibody titer of four doubling dilutions.
D)increase in the patient's titer of four doubling dilutions.

Answer 3

B
A fourfold rise in titer (an increase in the patient's titer of two doubling dilutions from acute to convalescent) is considered to be diagnostic of current infection.

Question 4

Antibody-mediated immune responses produced by specific proteins are generated by

A)lymphocytes of the T (thymus-derived) class.
B)lymphocytes of the B (bone marrow-derived) class.
C)neutrophils.
D)basophils.

Question 5

Opsonizing antibodies are

A)those that function by attaching to the surface of pathogens and contributing to their destruction by the lytic action of complement.
B)those that function by binding to and blocking surface receptors for host cells.
C)those that function by attaching to the surface of pathogens and making the pathogens more amenable to ingestion by phagocytic cells.
D)those that function by attaching to the surface of pathogens and contributing to their destruction by chemotaxis.

Question 6

The immunochemical test that involves the agglutination of an artificial carrier particle with antigen bound to its surface with antibody present in a specimen is referred to as

A)double immunodiffusion.
B)counterimmunoelectrophoresis.
C)particle agglutination.
D)enzyme immunoassay.

Question 7

Cell-mediated immune responses such as attacking and killing microorganisms or host cells damaged or infected are carried out by

A)lymphocytes of the T (thymus-derived) class.
B)lymphocytes of the B (bone marrow-derived) class.
C)neutrophils.
D)basophils.

Question 8

The antibody that is predominantly found in tears, saliva, and intestinal secretions is

A)IgG.
B)IgA.
C)IgM.
D)IgE.

Question 9

For most pathogens, to be diagnostic of current infection, there must be

A)a decrease in the patient's antibody titer of two doubling dilutions.
B)an increase in the patient's titer of two doubling dilutions.
C)a decrease in the patient's antibody titer of four doubling dilutions.
D)an increase in the patient's titer of four doubling dilutions.

Question 10

Specific proteins produced by cells of the immune system in response to the presence of foreign molecules that circulate in the serum and are present in secretions such as saliva are called

A)antigens.
B)immunoglobulins.
C)cytokines.
D)phagogens.

Question 11

The precipitin test that is widely used for detecting antibodies against fungal infection is referred to as

A)double immunodiffusion.
B)counterimmunoelectrophoresis.
C)particle agglutination.
D)enzyme immunoassay.

Question 12

The antibody that primarily protects body surfaces lined with mucous membranes such as the eyes and intestines is

A)IgG.
B)IgA.
C)IgM.
D)IgE.

Question 13

Antibodies that function by attaching to the surface of pathogens and contributing to their destruction by the lytic action of complement are called

A)opsonizing antibodies.
B)neutralizing antibodies.
C)complement-fixing antibodies.
D)chemotaxic antibodies.

Question 14

Complement-fixing antibodies are

A)those that function by attaching to the surface of pathogens and contributing to their destruction by the lytic action of complement.
B)those that function by binding to and blocking surface receptors for host cells.
C)those that function by attaching to the surface of pathogens and making the pathogens more amenable to ingestion by phagocytic cells.
D)those that function by attaching to the surface of pathogens and contributing to their destruction by chemotaxis.

Question 15

The antibody that has 10 antigen-binding sites is

A)IgG.
B)IgA.
C)IgM.
D)IgE.

Question 16

Antibodies that function by binding to and blocking surface receptors for host cells are called

A)opsonizing antibodies.
B)neutralizing antibodies.
C)complement-fixing antibodies.
D)chemotaxic antibodies.

Question 17

The study of the diagnosis of disease by measuring antibody levels in serum is called

A)immunology.
B)immunohematology.
C)serology.
D)immunocytology.

Question 18

A method that uses an electrical current to speed up migration of an antigen and antibody is referred to as

A)double immunodiffusion.
B)counterimmunoelectrophoresis.
C)particle agglutination.
D)enzyme immunoassay.

Question 19

The presence of this antibody usually indicates recent or active infection.

A)IgG
B)IgA
C)IgM
D)IgE

Question 20

Neutralizing antibodies are

A)those that function by attaching to the surface of pathogens and contributing to their destruction by the lytic action of complement.
B)those that function by binding to and blocking surface receptors for host cells.
C)those that function by attaching to the surface of pathogens and making the pathogens more amenable to ingestion by phagocytic cells.
D)those that function by attaching to the surface of pathogens and contributing to their destruction by chemotaxis.

Question 21

The difference between latex agglutination and coagglutination is

A)the type of particle used to carry the antibody.
B)the type of target organism involved.
C)that coagglutination is less specific but more sensitive.
D)coagglutination can be used for direct antigen detection but not latex agglutination.