viruses Flashcards
where is the only place a virus can reproduce
in host cells
T or F: viruses are alive
false; they’re not alive because they don’t meet all the requirements of living organisms
list the reasons why viruses aren’t alive
they’re acellular, don’t respond to stimuli, don’t undergo metabolic reactions, and they don’t maintain internal conditions through homeostasis
what nucleic acid type(s) can viruses have
ss DNA or ss RNA
ds DNA or ds RNA
what surrounds the genome of a virus
a protein coat called a capsid
what is a capsid
a protein coat that surrounds the genome of a virus
what is the name of the proteins that make up the capsid
protomers
what are the three types of capsid symmetry
helical, icosahedral, complex
describe helical capsids
the protomers self-assemble in a helical/spiral arrangement to produce a rod structure
give an example of a virus with helical capsid
tobacco mosaic virus
describe icosahedral capsids
a polyhedron with 20 equilateral triangular faces and 12 vertices
give an example of a virus with an icosahedral capsid
human papilloma virus (HPV)
describe a complex capsid
they have complicated structures and may possess tails and other structures
give an example of a virus with a complex capsid
T4 bacteriophage (they infect E coli)
what layer do some bacteria have that surrounds the capsid
viral envelope
what is the viral envelope made of
protein, lipids, and carbs
what do some enveloped viruses have that project from the surface of the envelope
spikes
what is a virus called that doesn’t have its capsid covered by an envelope
naked or nonenveloped
advantage to having an envelope?
helps the virus to evade the host’s immune system
disadvantage to having an envelope?
more sensitive to environmental conditions (ie antimicrobial agents)