17.
Polyvinyl alcohol (PVA) is a mixture used to:
a. Fix and preserve the operculum on flukes and tapeworms for purposes of
identification.
b. Fix and preserve trophozoites of intestinal amoebic organisms.
c.
Fix and preserve ova of human cestodes.
d. Fix and preserve for identification adult forms of Macracanthorrhynchus
hirudinaceous.
18.
Quensel's solution is used to demonstrate:
a. Motile trophozoites on wet mount slide preparations.
b. Ova of Echinococcus multilocularis.
c.
Cercaria in cases of suspected trematode infestation.
d. Cilia in the class Ciliophora or Ciliata.
19.
A positive Hemacult test for occult blood is represented by a:
a. Yellow color on the filter paper.
b. Blue color around the tablet within two minutes.
c.
Reddish color which persists for 5 minutes.
d. Green color on the filter paper
20.
Which of the following situations is considered as a possible disadvantage in the
application of the Formalin-Ethyl-Acetate concentration technique?
a. Operculated eggs and those of Schistosoma are not easily recovered.
b. Helminth larvae cannot be concentrated.
c.
Caution must be exercised when using ethyl acetate.
d. All of the above.
MD0841
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