In an immunodiffusion test, a strip of filter paper containing diphtheria antitoxin is placed on a solid culture medium. Then bacteria are streaked perpendicular to the filter paper. If the bacteria are toxigenic,
a. the filter paper will turn red.
b. a line of antigen–antibody precipitate will form.
c. the cells will lyse.
d. the cells will fluoresce.
e. none of the above

The examples in questions 1 and 2 are

a. direct tests.

b. indirect tests.

Use the following choices to answer questions 4 and 5:

a. anti-Brucella

b. Brucella

c. substrate for the enzyme

Which is the third step in a direct ELISA test?

NAME IT A purified protein from Mycobacterium tuberculosis is injected into a person’s skin. A hardened, red area develops around the injection site within 3 days.

Use the following choices to answer questions 4 and 5:

a. anti-Brucella

b. Brucella

c. substrate for the enzyme

Which item is from the patient in an indirect ELISA test?

Use the following choices to answer questions 1 and 2:

a. hemolysis

b. hemagglutination

c. hemagglutination inhibition

d. no hemolysis

e. precipitin ring forms

Patient’s serum, influenza virus, sheep red blood cells, and anti-sheep red blood cells are mixed in a tube. What happens if the patient has antibodies against influenza?

Use the following choices to answer questions 1 and 2:

a. hemolysis

b. hemagglutination

c. hemagglutination inhibition

d. no hemolysis

e. precipitin ring forms

Patient’s serum, Chlamydia, guinea pig complement, sheep red blood cells, and anti-sheep red blood cells are mixed in a tube. What happens if the patient has antibodies against Chlamydia?

Discuss the roles of antibodies and antigens in an incompatible tissue transplant.

Which of the following is not a function of antibodies?

a. Opsonization

b. Activating complement proteins

c. Activating T helper cells

d. Enhancing phagocytosis

e. Antigen neutralization