The antibody that is predominantly found in tears, saliva, and intestinal secretions is:
a. IgG.
b. IgA.
c. IgM.
d. IgE.
Monoclonal antibodies are those that:
a. react with many different types of anti-gens.
b. react with many species of bacteria within the same genus.
c. are produced by the offspring of a single hybrid cell.
d. can be produced from many different spe-cies of host organisms.
Complement-fixing antibodies are those that function by:
a. attaching to the surface of pathogens and contributing to their destruction by the lytic action of complement.
b. binding to and blocking surface receptors for host cells.
c. attaching to the surface of pathogens and making the pathogens more amenable to ingestion by phagocytic cells.
d. attaching to the surface of pathogens and contributing to their destruction by che-motaxis.
Opsonizing antibodies are those that function by:
a. attaching to the surface of pathogens and contributing to their destruction by the lytic action of complement.
b. binding to and blocking surface receptors for host cells.
c. attaching to the surface of pathogens and making the pathogens more amenable to ingestion by phagocytic cells.
d. attaching to the surface of pathogens and contributing to their destruction by che-motaxis.
For most pathogens to be diagnostic of current infection, there must be a(n) _____ in the patient's antibody titer of _____ doubling dilutions.
a. decrease; two
b. increase; two
c. decrease; four
d. increase; four