The ability of a virus to produce disease can result from a variety of mechanisms. Which one of the following mechanisms is LEASTlikely?
A. cytopathic effect in infected cells
B. malignant transformation of infected cells
C. immune response to virus-induced antigens on the surface of infected cells
D. production of an exotoxin that activates adenylate cyclase
E. apoptosis
Reasonable mechanisms for viral persistence in infected individuals include all of the following EXCEPT
A. destroy ofimmune cells by viruses
B. virus-mediated inhibition of host DNA synthesis
C. integration of a provirus into the genome of the host
D. host tolerance to viral antigens
E. mutation of viral antigens
Virus-infected cells often develop morphologic changes referred to as cytopathic effects. Which of the following statements about virus-induced cytopathic changes is most accurate?
A. They are pathognomonic for an infecting virus.
B. They are rarely associated with cell death.
C. They may include giant cell formation.
D. They can only be seen with an electron microscope.
Laboratory infections can be acquired when working with viruses unless good laboratory safety practices are followed. Which of the following is not a good biosafety practice?
A. Use of biosafety hoods
B. Use of laboratory coats and gloves
C. Avoidance of pipetting by mouth
D. Flushing experimental waste down laboratory sink
E. Not eating or drinking in the laboratory
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