Choose the best answer

1			The conquest of the Aztec Empire in Mexico was made possible by a ______ epidemic that ravaged Mexico City.
			A)	Measles
			B)	Smallpox
			C)	Rabies
			D)	Influenza
			E)	Chickenpox
2			Edward Jenner began inoculating humans with material from _______ lesions.
			A)	Smallpox
			B)	Avianpox
			C)	Cowpox
			D)	Chickenpox
			E)	Dogpox
3			Viruses require ______ for growth.
			A)	Plants
			B)	Animals
			C)	Bacteria
			D)	Living cells
			E)	Fungi
4			Holes produced in bacterial “lawns” by viruses are called
			A)	Colonies
			B)	Plaques
			C)	Patches
			D)	Lysis
			E)	Clearance
5			Which is NOT true of virions?
			A)	Contain DNA
			B)	Contain RNA
			C)	Are extracellular
			D)	Reproduce independently
			E)	Induce host metabolism
6			Which of the following are obligate intracellular parasites?
			A)	Viruses
			B)	Chlamydia
			C)	Rickettsia
			D)	All of the above
			E)	None of the above
7			Plant viruses may be cultivated in
			A)	Tissue culture
			B)	Cultures of separated cells
			C)	Cultures of protoplants
			D)	Whole plants
			E)	All of the above
8			Viruses can be purified based on their size and density by use of
			A)	Gradient centrifugation
			B)	Differential centrifugation
			C)	Precipitation
			D)	Filtration
			E)	All of the above
9			Which of the following may affect proteins and nucleic acids, but NOT viruses?
			A)	Denaturation
			B)	Enzyme treatment
			C)	Heat
			D)	Drastic pH changes
			E)	All of the above
10			The most popular indirect method of counting virus particles is
			A)	Microscopically
			B)	By hemagglutination assay
			C)	By plaque-assay
			D)	By counting plaque-forming units
			E)	By colony counting
11			What kind of embryo is often used for viral assays?
			A)	Mouse
			B)	Rat
			C)	Cat
			D)	Dog
			E)	Chicken
12			Enveloped viruses have a ______ shape.
			A)	Icosahedral
			B)	Helical
			C)	Hexagonal
			D)	Roughly spherical
			E)	Complex
13			The most efficient way to enclose a space is within a/an
			A)	Sphere
			B)	Cube
			C)	Icosahedron
			D)	Helix
			E)	None of the above
14			Usually viruses are separated into several large groups based primarily on
			A)	Nature of the host
			B)	Nucleic acid characteristics
			C)	Capsid symmetry
			D)	Presence of an envelope and ether sensitivity
			E)	Diameter of the viroin or nucleocapsid