PHMY 610 EXAM 2 MATERIAL QUESTIONS
AND ANSWERS
tobacco mosaic virus - ANSWER the first virus to be discovered (1892)
They used a special filter to filter out everything except the virus.
1898 - ANSWER the year Beijerinck first called the tobacco mosaic
virus a "virus"
virus - ANSWER Latin for poison
false - ANSWER true or false?
viruses are metabolically active outside a host cell.
metabolically inert - ANSWER not able to replicate outside of a human
cell
parasite - ANSWER A virus is a _______ because it can't replicate
outside of a host cell.
inert - ANSWER viruses are metabolically ______ outside the host cell.
capsid - ANSWER Outer protein coat of a virus
(bacteria have biofilm, viruses have this)
enveloped virus - ANSWER a virus that has a membrane composed
mostly of host material surrounding the capsid is called a...
true - ANSWER True or False:
Viruses can have DNA or RNA.
shape - ANSWER Viruses were originally classified by ______.
,body system - ANSWER Today, viruses are classified by which ______
________ they infect.
naked - ANSWER viruses that don't have a capsid or envelope
spikes - ANSWER attachment proteins on enveloped viruses.
These allow the viruses to hook onto human cells.
These can trigger the immune system.
segmented - ANSWER ______ viruses have more than one RNA
molecule.
nonsegmented - ANSWER Will DNA viruses be segmented or
nonsegmented?
RNA - ANSWER All segmented viruses must be ___ viruses.
isometric - ANSWER Viral shape that looks like a circle
helical - ANSWER Viral shape that looks a little more like a rod
pleomorphic - ANSWER Viral shape that's pretzel shaped
small - ANSWER viruses are so easy to spread because they're so
______.
ebola - ANSWER One of the biggest viruses
attachment - ANSWER Step 1 of host cell infection:
Virus uses spike proteins to grab onto host cell.
true - ANSWER True or false:
A virus will both integrate into and degrade host DNA.
lysogeny - ANSWER parasitic phase of viral replication; the virus fully
integrates its genetic material into the host genetic material, so it can
undergo replication.
Followed by assembly and release phase.
,budding - ANSWER Another name for viral release phase; new virions
are released.
virion - ANSWER Product of infection: a fully formed virus that is able to
establish an infection in a host cell
lytic phase - ANSWER the phase where the virus multiplies rapidly and
causes the host cell to burst. Kills the host cell within 1 generation.
lysogenic phase - ANSWER the phase where the virus does not kill the
host cell, but integrates into DNA (prophage/*provirus*) or remains
independent.
the virus still multiplies, but the host cell gets to live.
lytic - ANSWER A virus can use the host cell for several lysogenic
phases until bursting it in one final ______ phase.
bacteriophage - ANSWER the type of virus that infects bacteria
lytic - ANSWER bacteriophages kill bacteria through the ____ phase.
antibiotics - ANSWER bacteriophages are being researched as
alternatives to __________.
true - ANSWER True or False:
During the lysogenic phase, when bacteriophage viruses are inserting
their genetic material into the bacteria's genes, it could inadvertently
create resistance mechanisms and strengthen the bacteria.
lytic - ANSWER In order to kill the bacteria, phages should mostly use
the _____ phase.
14 - ANSWER There are __ RNA virus families
7 - ANSWER There are _ DNA virus families.
, cultivated - ANSWER viruses can be _________ in living animals,
embryonated chicken eggs, or cell/tissue culture (in vitro).
plaque-forming units (PFU) - ANSWER each plaque corresponds to a
single virus; what you count in a plaque assay
electron microscope - ANSWER you can count viruses using an
_______ ________ and you can get a density with that
ID50 - ANSWER infective dose for 50% of the population; how much
virus would you need to infect someone?
LD50 - ANSWER lethal dose for 50% of the population; how much
virus would you need to kill someone?
hemagglutination - ANSWER a way of detecting viruses (like
Adenovirus) because they agglutinate to RBCs when added to culture
PCR - ANSWER most commonly used clinical method of quantifying
the amount of virus in the body.
acute - ANSWER infection of short duration; symptoms are caused by
tissue damage (lytic)
naked - ANSWER _______ viruses cause more lysis than enveloped
viruses.
These are more likely to cause acute infections.
days to weeks - ANSWER how long does it usually take to recover from
an acute infection?
IgM - ANSWER the antibody that means ACTIVE infection (early,
acute)
IgG - ANSWER the antibody that means you've had the infection
before and you're protected now.
persistent - ANSWER viruses that are present in the body long-term
AND ANSWERS
tobacco mosaic virus - ANSWER the first virus to be discovered (1892)
They used a special filter to filter out everything except the virus.
1898 - ANSWER the year Beijerinck first called the tobacco mosaic
virus a "virus"
virus - ANSWER Latin for poison
false - ANSWER true or false?
viruses are metabolically active outside a host cell.
metabolically inert - ANSWER not able to replicate outside of a human
cell
parasite - ANSWER A virus is a _______ because it can't replicate
outside of a host cell.
inert - ANSWER viruses are metabolically ______ outside the host cell.
capsid - ANSWER Outer protein coat of a virus
(bacteria have biofilm, viruses have this)
enveloped virus - ANSWER a virus that has a membrane composed
mostly of host material surrounding the capsid is called a...
true - ANSWER True or False:
Viruses can have DNA or RNA.
shape - ANSWER Viruses were originally classified by ______.
,body system - ANSWER Today, viruses are classified by which ______
________ they infect.
naked - ANSWER viruses that don't have a capsid or envelope
spikes - ANSWER attachment proteins on enveloped viruses.
These allow the viruses to hook onto human cells.
These can trigger the immune system.
segmented - ANSWER ______ viruses have more than one RNA
molecule.
nonsegmented - ANSWER Will DNA viruses be segmented or
nonsegmented?
RNA - ANSWER All segmented viruses must be ___ viruses.
isometric - ANSWER Viral shape that looks like a circle
helical - ANSWER Viral shape that looks a little more like a rod
pleomorphic - ANSWER Viral shape that's pretzel shaped
small - ANSWER viruses are so easy to spread because they're so
______.
ebola - ANSWER One of the biggest viruses
attachment - ANSWER Step 1 of host cell infection:
Virus uses spike proteins to grab onto host cell.
true - ANSWER True or false:
A virus will both integrate into and degrade host DNA.
lysogeny - ANSWER parasitic phase of viral replication; the virus fully
integrates its genetic material into the host genetic material, so it can
undergo replication.
Followed by assembly and release phase.
,budding - ANSWER Another name for viral release phase; new virions
are released.
virion - ANSWER Product of infection: a fully formed virus that is able to
establish an infection in a host cell
lytic phase - ANSWER the phase where the virus multiplies rapidly and
causes the host cell to burst. Kills the host cell within 1 generation.
lysogenic phase - ANSWER the phase where the virus does not kill the
host cell, but integrates into DNA (prophage/*provirus*) or remains
independent.
the virus still multiplies, but the host cell gets to live.
lytic - ANSWER A virus can use the host cell for several lysogenic
phases until bursting it in one final ______ phase.
bacteriophage - ANSWER the type of virus that infects bacteria
lytic - ANSWER bacteriophages kill bacteria through the ____ phase.
antibiotics - ANSWER bacteriophages are being researched as
alternatives to __________.
true - ANSWER True or False:
During the lysogenic phase, when bacteriophage viruses are inserting
their genetic material into the bacteria's genes, it could inadvertently
create resistance mechanisms and strengthen the bacteria.
lytic - ANSWER In order to kill the bacteria, phages should mostly use
the _____ phase.
14 - ANSWER There are __ RNA virus families
7 - ANSWER There are _ DNA virus families.
, cultivated - ANSWER viruses can be _________ in living animals,
embryonated chicken eggs, or cell/tissue culture (in vitro).
plaque-forming units (PFU) - ANSWER each plaque corresponds to a
single virus; what you count in a plaque assay
electron microscope - ANSWER you can count viruses using an
_______ ________ and you can get a density with that
ID50 - ANSWER infective dose for 50% of the population; how much
virus would you need to infect someone?
LD50 - ANSWER lethal dose for 50% of the population; how much
virus would you need to kill someone?
hemagglutination - ANSWER a way of detecting viruses (like
Adenovirus) because they agglutinate to RBCs when added to culture
PCR - ANSWER most commonly used clinical method of quantifying
the amount of virus in the body.
acute - ANSWER infection of short duration; symptoms are caused by
tissue damage (lytic)
naked - ANSWER _______ viruses cause more lysis than enveloped
viruses.
These are more likely to cause acute infections.
days to weeks - ANSWER how long does it usually take to recover from
an acute infection?
IgM - ANSWER the antibody that means ACTIVE infection (early,
acute)
IgG - ANSWER the antibody that means you've had the infection
before and you're protected now.
persistent - ANSWER viruses that are present in the body long-term
