viruses?
Identify all the methods that a virus can use to gain entry into an animal cell.
-Engulfment/phagocytosis of the virus -Fusion of the viral envelope and the cell membrane
Identify any of the following pathways which could produce proteins used by viruses.
-Host DNA --> mRNA --> proteins used by viruses -Viral positive-ssRNA --> proteins used by viruses -Viral positive-ssRNA --> Viral negative-ssRNA --> many Viral positive-ssRNAs --> proteins used by viruses
Identify any of the following pathways which could produce proteins used by viruses.
-Host DNA --> mRNA --> proteins used by viruses -Viral positive-ssRNA --> proteins used by viruses -Viral positive-ssRNA --> Viral negative-ssRNA --> many Viral positive-ssRNAs --> proteins used by viruses
The persistence of bacteriophages within host cells is called
-Lysogeny
Which of the following is used to describe the phage DNA that is latently incorporated into the bacterial host genome?
-Prophage
Which factor enables certain laboratory animals to propagate viruses more readily than others?
-Receptor specificity between virus and particular animal hosts
Identify the commonalities between temperate phages and lytic phages.
-Release
Which of the following are cytopathic effects in virally infected animal cells?
-Syncytia -Inclusion bodies
What name is given to a phage "type" which can incorporate itself into the host genome as a lysogenic prophage?
-Temperate
Lysogenic conversion is when
-a bacterium acquires a new trait from its temperate phage
Which viral stage occurs first?
-adsorption
Mature virus particles are constructed from nucleic acid and protein during the ______ phase of the viral life cycle.
-assembly
Plaques are associated with which of the following?
-bacteriophage infection of bacteria
Viruses can cause cancer by
-causing a loss of growth regulation -introducing oncogenes to a host cell
Which of the following would indicate that a virus is infecting a tissue culture cell line
-cells degenerate and lyse
Viruses that remain hidden in cells and periodically become reactivated, such as herpes simplex, are in a
-chronic latent
Most bacteriophages contain which type of nucleic acid?
-dsDNA
Identify all the types of nucleic acid genomes which have been discovered carried by various bacteriophages.
-dsDNA ssDNA ssRNA
Identify all the types of nucleic acid genomes which have been discovered carried by various bacteriophages.
-dsDNA -ssDNA -ssRNA
Viral DNA polymerase genes are expressed during the
-early
Most bacteria engulf bacteriophages as part of the phage replication strategy.
-false
True or false: The interior of eggs normally contains non-pathogenic bacterial cells but no viruses.
-false
Viral transformation by oncogenic viruses implies that the
-host cell is changed
One type of cytopathic effect is the accumulation of ______, compacted masses of viruses or damaged cell organelles within an infected host cell.
-inclusion bodies
A prophage is activated and enters the lytic cycle through the process called
-induction
What term is used to define the process of a prophage being activated and entering into the lytic cycle?
-induction
Which of the following are in vivo methods for viral cultivation?
-inoculating chicken eggs with viruses -inoculating mice with viruses
A bird egg containing an embryo is useful for the cultivation of animal viruses because it
-is a sterile environment -contains tissues that support viral multiplication
Which of the following describes a process of bacteriophage infection which could result in a new disease trait (such as a toxin) in the infected bacterium?
-lysogenic conversion
Which term refers to the persistence of bacteriophages within host cells?
-lysogeny
Which of the following describes the "clear" area where a virus-infected cell lysed and infected all the neighboring cells and lysed those too?
-plaque
During the lysogenic cycle
-prophage
During the lysogenic cycle, viral DNA enters an inactive ______ state, during which it is inserted into the bacterial chromosome.
-prophage
Toxins of the bacteria responsible for diphtheria, cholera, and botulism are actually produced by
-prophages
Most host cell receptors that viruses attach to are actually that the cell uses in normal function.
-proteins
In the viral synthesis phase, late-stage mRNAs are produced by using ______ as a template to make many new
-ssRNA; +ssRNAs
A bacteriophage that does not immediately lyse or change the appearance of host cells is called a(n)
-temperate
botulism are made more virulent by bacteriophages known as
-temperate
Which step in the life cycle of an animal virus is not needed in the life cycle of a bacteriophage?
-uncoating
Change in a cell line monolayer is indicative of which of the following?
-virally infected cells
A virus that parasitizes other viruses that are infecting the same host cell is called a
-virophage
List 3 purposes of viral cultivation
1 to study 2 to prepare vaccines 3 to identify viruses in clinical specimens
Replication of viruses
1Adsorption 2Biosynthesis of viral components 3Penetration 4Assembly
replication
1Adsorption 2Biosynthesis of viral components 3Penetration 4Assembly
List the correct order of viral life cycle phases, starting with the first at the top.
1adsorption 2penetration/uncoating 3synthesis 4assembly 5release
List the correct order of viral life cycle phases
1adsorption 2penetration/uncoating 3synthesis 4assembly 5release
Mammalian viruses capable of initiating tumors are called
Oncoviruses
Which of the following is used to describe the phage DNA that is latently incorporated into the bacterial host genome?
Prophage
Lysogenic conversion is when
a bacterium acquires a new trait from its temperate phage
The viral process of attaching to the host cell receptor for the virus is called
adsorption
The virus shown here binding to host cell proteins is in the__stage of the viral life cycle
adsorption
Which viral stage occurs first?
adsorption
Synctia
and inclusion bodies are two types of effects in virus-infected cells.
Two terms that have the same meaning
are cell culture and tissue culture.
Mature virus particles are constructed from nucleic acid and protein during the ______ phase of the viral life cycle.
assembly
New virions are built from their components during the
assembly
Mature enveloped viruses are released from host cells via
budding
Viruses can cause cancer by
causing a loss of growth regulation introducing oncogenes to a host cell
Which of the following would indicate that a virus is infecting a tissue culture cell line?
cells degenerate and lyse
Viruses that remain hidden in cells and periodically become reactivated, such as herpes simplex, are in a
chronic latent
Most RNA viruses will assemble the virion within the host cell's
cytoplasm
Most bacteriophages contain which type of nucleic acid?
dsDNA
Viral DNA polymerase genes are expressed during the
early
In penetration by ______, the entire virus is engulfed by the cell and enclosed in a vacuole or vesicle.
endocytosis
The 2 principal processes by which viruses penetrate host cells are
endocytosis (engulfment) and direct fusion.
The 2 principal processes by which viruses penetrate host cells are
endocytosis (engulfment) and direct fusion.
Which types of viruses are released by budding?
enveloped viruses
Most bacteria engulf bacteriophages as part of the phage replication strategy.
false
True or false: The interior of eggs normally contains non-pathogenic bacterial cells but no viruses.
false
Viral transformation by oncogenic viruses implies that the
host cell is changed
the limitation of the type o cell that a virus can invade is called the
host range
One type of cytopathic effect is the accumulation of ______, compacted masses of viruses or damaged cell organelles within an infected host cell.
inclusion bodies
A prophage is activated and enters the lytic cycle through the process called
induction
What term is used to define the process of a prophage being activated and entering into the lytic cycle?
induction
Viral capsid proteins are synthesized during the _____ stage of the synthesis phase of the viral life cycle.
late
Which of the following describes a process of bacteriophage infection which could result in a new disease trait (such as a toxin) in the infected bacterium?
lysogenic conversion
Which term refers to the persistence of bacteriophages within host cells?
lysogeny
Cultured cells grow in the form of a ____a single confluent sheet of cells that supports viral multiplication.
monolayer
Viruses that lead to cancer in infected hosts are called
oncoviruses
Viruses have tropisms, that is they can infect
only cells of a certain tissue type
Which of the following describes the "clear" area where a virus-infected cell lysed and infected all the neighboring cells and lysed those too
plaque
During the lysogenic cycle
prophage
During the lysogenic cycle, viral DNA enters an inactive ______ state, during which it is inserted into the bacterial chromosome.
prophage
Toxins of the bacteria responsible for diphtheria, cholera, and botulism are actually produced by
prophages
Most host cell receptors that viruses attach to are actually that the cell uses in normal function.
proteins
The virus buds off the membrane and picks up an envelope and spikes during which stage of the viral life cycle?
release
Some laboratory animals can propagate viruses in the laboratory more readily than others because many viruses exhibit host
specificity
The fusion of multiple damaged host cells into single large cells containing multiple nuclei produces
syncytia
A bacteriophage that does not immediately lyse or change the appearance of host cells is called a(n)
temperate
Some deadly human pathogens such as diphtheria cholera and botulism are made more virulent by bacteriophages known as
temperate
Viruses that can infect only certain tissues are described as having a tissue specificity or
tropism
Viruses can usually only adsorb to cells of specific tissue types and these specificities are called
tropisms
Which step in the life cycle of an animal virus is not needed in the life cycle of a bacteriophage?
uncoating
Virus cultivation is an important activity because viral stocks are needed for the preparation of some
vaccines
Which is most important for attachment of a virus to a host cell?
viral specificity for host receptors
Change in a cell line monolayer is indicative of which of the following?
virally infected cells
A virus that parasitizes other viruses that are infecting the same host cell is called a
virophage
Identify all the methods that a virus can use to gain entry into an animal cell.
Engulfment/phagocytosis of the virus -Fusion of the viral envelope and the cell membrane
which of the host cell structures must usually be specific for adsorption
Glycoprotein
The persistence of bacteriophages within host cells is called
Lysogeny
Which of the following is the term for an animal virus that has integrated its DNA into the DNA of a host cell?
Provirus
Which factor enables certain laboratory animals to propagate viruses more readily than others?
Receptor specificity between virus and particular animal hosts
Identify the commonalities between temperate phages and lytic phages.
Release
What name is given to a phage "type" which can incorporate itself into the host genome as a lysogenic prophage?
Temperate