Cryptococcus neoformans is widely distributed in nature, and aerosolization is a prerequisite to most infections. This organism is most often associated with exposure to:
a. contaminated soil.
b. pigeon excreta.
c. contaminated food.
d. rat excreta.
B
C. neoformans exists as a saprobe in nature and is most often found associated with avian excreta, particularly that of pigeons. Numerous reports substantiate the hypothesis that pigeon habitats serve as reservoirs for human infection. The pigeon manure apparently serves as an enrichment factor for C. neoformans because of its composition. C. neoformans is believed to be widely dis-tributed in nature, and aerosolization is a prerequisite to most infections.
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The technique by which DNA, RNA, or protein molecules are separated in a gel that is subjected to an electric field is
called ____.
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Who was first scientist to identify and characterize DNA?
a. Rosalind Franklin b. Linus Pauling c. Francis Crick d. Friedrich Miescher
Which of the following statements regarding lichens is FALSE?
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