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97 Cards in this Set

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  • Back
Virus sizes are from______ to ________with smallpox being one of the largest to parvo being one of the smallest
20nM To 250nM
Virus's are made from particles of _____ and _______,often with a covering membrane.
nucleic acid,protein
a virus that eats bacteria is called______?
the use of ___________was used to cultivate virus;s
fertilized chicken eggs
the reason that the electron microscope has such a high resolving power is the ________wavelenght
Sizes a eukaryotic cell:___________nm
E. coli bacterium:__________nM
parvo virus:_________nM
a nm is a ___________of a meter
some virus's such as the tobacco virus and rabies have the shape of a _________.
a helix is a tightly wound corkscrew that looks like a __________.
other virus's such as herpes simplex and polio have the shape of ____________.
An Icosahedron is a polyhedron with _______ triangular faces and ______corners.
20 ;;;12
certain virus's have a combination of helical and icosahedral symmetry, a construction described as ____________>
All virus consist of a core of nucleic acid called the __________ and a surrounding coat called a _________.
The genime contains either ______ or ______ but not both.
The genome is usually folded and condensed in ________virus's.And ______in helical fashion in helical virus's
icosahedral ;;coiled
The genome is usually folded and condensed in ________virus's.And ______in helical fashion in helical virus's
icosahedral ;;coiled
Generally the capsid is subdivided into individual protein subunits called________.
The ________of capsomeres is characterized for a particlar virus
The capsid provides a protective covering for the genome because the const. of its amino acidsresists ______,_______and other environmental factors
The capsid plus the genome is called_____-
Many virus;s are surrounded by a flexable membrane known as an _________.
The envelope is composed of ________and ___________.
lipids ,,proteins
The envelope is aquired from the _______during replication and is unique toeach type of virus
In some virus;s suchas influenza and measles ,the envelope contains functional projections known as ________
Acompletely assembled and infectious virus outside its host cell is known as__________
Attachment: The bacteriophage (virus) attaches to its host cell(bacterium) at a complimentary ______________.
receptor site
Penetration:The _________ remains outside the cell , while the viral _________enters the cells cytoplasm>(This phase varies among virus's)
New virus's are released from the host cell to infect adjacent cells and begin a new cycle of replication.THis is called___________.
aproximate time for the replication process of bacteriophage is________to _________minutes and called ____________.
virus attachment is a ____________ event.
The ___________ in the virion contains only a few of the many _________needed for viral synthesis and replication.Therefore it's dependendece on the host cell is substantial.
nucleic acid ,,,genes
The actual attachment consists of a weak _________union between virion and ____________.
chemical ,,,receptor site
In the penetration phase the ________of the phage releases the enzyme________ to dissolve a portion of the bacterial cell wall.
for a number of minutes in the biosynthesis phase no viral parts are present and this is called __________.
eclipse period
for bacteriophages the release phase is also called________
lysis stage
In the attachment phase of animal virus's:the receptor sites exist on the host ___________rather than the cell wall.Also animal virus's have no _______so the receptor sites are evenly distributed over the entire surface of the ________.
cell membrane ,,tail,,,,capsid
The number of new virus's made in bacteriophage replication is ____ to ____ and this number is called ________.
50 ,,,200,,,,,burst size
The receptor sites vary from person to person which may account for different ____________ to a particular virus.
bacteriophages inject their DNA into the host cell cytoplasm,but animal viruses are usually taken in_________ into the cytoplasm.
Penetration is also different in animal viruses ,and enter by two major methods 1. the spikes interact with receptor sites, the envelope blends with lipids on the cell membrane and the ________passes into the host cells cytoplasm.2an interaction between spikes and receptor sites takes place and a __________ forms around the virus.
nucleocapsid ,,,,vesicle
Animal virus: uncoating takes place after the nucleocapsid has entered the cytoplasm , the protein coat is separared from the nucleic acid by the activity of __________.
_________ is the workhorse for DNA
Replication of DNA viruses: DNa gets in nucleus and takes over __________.
_________is made in the cytoplasm and the _________is made in the nucleus
RNA viruses follow a slightly different pattern. The RNA can act as a messenger RNA molecule and immediatly begin supply the codes for protein synthesis .Such a virus is called________,or __________.
positive stranded Rna virus,,,,sense virus
In other RNA viruses the Rna strand is used as a template to synthesize a complimentary strand of RNA.The latter is then used as a messenger RNA molecule for protein synthesis. Then original {RNA strand is said to have "antisense"and the virus is therefore an ____________.IT is also called a_____________.
antisense virus,,,,negative-stranded RNA virus.
Measle viruses are ___________viruses whereas polio viruses are _________.
antisense(negative stranded),,,sense(positive stranded)
Retrovirus carry their own enzyme called ________________.The enzyme uses the viral DNA as a template to synthesize ____________.
reverse transcriptase,,,,,single stranded DNA
a virus whose reverse transcriptase uses RNA as a template to synthesize DNA for incorporation into a cells nucleic acid is called __________/.
The DNA now migates to the cell nucleus and integrates into one of the host cell's chromosomes,where it is known as a _____________.
The virus pushes through the membrane forcing a portion of the membrane ahead of it and around it resulting in an envelope.This process is called _________and need not necessarily kill the cell during the virus;exit.
unenveloped viruses<when they leave the cell>the cell membrane ____________a process that leads to cell death.
The condition in which viruses and bacteria coexist whithout damage to each other is called _________.
when bavteriophages are involved the phage DNA in the lysogenic state is called a ________;when an animal virus(such as a retrovirus)is involved the viral DNA is known as a _________.
Viruses in the lysogenic state for example are __________ to body defenses since the body's antibodies cannot reach them (antibodies do not penetrate into cells).
In _________ the virus is propagated each time the cell's chromosome is reproduced.and the prophage or provirus can confer new properties on the infected cell.such as when a toxcin-encoding proghage infects a bacterium.(Exp.)Clostridium botulinum.
lysogeny ,,,
A phenomenon traced to lysogeny is ___________. In this process a fragment of DNA from one cell is transferred to a second cell in combination with bacteriophages DNA . Cancer may develope when a virus enters a cell and assumes a__________ relationship with that cell.
specialied transduction,,,,lysogenic
classification:_________DNA families
:____________RNA families
:____________misc. famillies
A common method of of cultivating viruses is to inoculate them into ____________.viral replication is detected by either the death of the embryo,__________ or the formations of characteristic lesions at the site of inoculation.
fertilized chicken eggs,,cell damage
To prepare a __________-cells are separated from a tissue with enzymes and are suspended in a solution of nutrients,growth factors ph buffers, and salts.When viruses replicate nthese cells a noticeable deterioration occurs.This is called a _______________.
tissue culture,,,,cytopathic effect
When proviruses(lysogeny)goes into an active state it is called _________.
lytic cycle
__________virus always kills host cell
DNA to RNA is done with the enzyme _________which is called areplicator
Replication enzyme of RNA virus uses the enzyme __________.
RNA polymerase
Since this RNA virus cannot supply the codes for making its own proteins untill it makes a complimentary strand of RNA it is called an___________virus or a ___________
antisense,,,,, negative stranded RNA virus
Retroviruses carry there own enzyme called_________________and uses the RNA as template to make single strand _______and once formed the_______serves as temp. to form another single strand of ________.these twist to a double helix then the _______goes to cell nuke and integrates with chrome.where it is known as a __________.
Provirus: the virus pushes through the membrane forcing a portion of the membrane ahead of it and around it .This is called __________ and need not necessarily kill the cell.
unenveloped viruses rupture the cell membrane and usually lead to cell ______
Living cells need not be the only way for repl. to occur but ________may be enough for viral repl..
cell debris
____________stage -can sit in DNA and not harm cell
__________stage--actively causing viruses to be made.
the phage DNA in the lysogenic state is called a__________
viruses in the lysogenic state are ______to the bodies antibodoies.
Lysogenic state ::the virus is ______ each time the cell goes thru mitosis.example clostridium botulinum
IN HIV the __________harbor the provirus
T-lymphocytes (T_cells)
cancer may develope when a virus enters a cell and assumes a ___________relationship and the proteins encoded bring profound change
the process where a fragment of DNA from one cell is transphered to a second cell incombination with a bacteriophage DNA is called _________.
specialized transduction
In detection of viruses inoculation is done in_________and ________.
fertilized eggs,,,tissue cultures
an indirect method for detecting a virus is to search for viral antibodies in _______
certain viruses have the ability to agglutinate _______.this is called ________.
red blood cells,,,hemagglutination
In the hemagglutination-inhibition test ___________are combined with _______from patient. If the serum contains antibodies mfor that virus then antibodies coat the virus and then combined with red blood cells ,noaglutination means pos. for that virus
known viruses ,,, serum(contains antibodies)))
sometimes viruses leave signs like those of rabid animals contain cytoplasmic granules called ________ and cells from herpes simlex contain granules known as __________.
Negri bodies,,,Lipshultz bodies
Infectious mononucleosis is characterized by large no. of swollen lymphocytes with foamy,vaculated cytoplasm called____________.
Downey cells
_________is a series of bright red patches with white pimple like centers.Measles
Koplik spots
No growth spot in a culture of a certain bacteria would show a bacteriophage present and these spots are called ___________.
__________postulate is for viruses
changes in a cell due to virus growing is called____________
Cytopathic effect(cick embryo's)
antibodies clump viruses into large masses to be removed by ________.
Normal viruses cannot be defened against by common_________.
_________interferon(substances made by infected cells) is the only one that will work on humans.interferons also mobilize natural killer cells which attck _____ cells
Viral vaccines can be made from ______ and ______which are virus designed to replicate at a slow rate and stimulate the immune system longer
inactivated viruses,,,,attenuated viruses
Cancer cells differ from normal in three ways 1.mitosis more frequently 2.stick together less firmly.and 3. cells revert to an earlyer stage of their developement and this is called____________
cancer cells fail to exhibit __________that is they do not adhere tightly to one another.sometimess they________or spread to other parts of the body.
contact inhibition,,,metastasize
normal genes,called______________are the forerunners of ______________(cancer genes)
epstein -barr virus is known to precurser Burkitts ____________.
________are tiny fragments of nucleic acid that can cause disease (mostly in plants)
________are described as proteinaceous infectious particles thought to cause disease such as mad cow.
Brain tissue developes a spongelike appearance with empty areas of dead tissue from prions .These are called ___________________.
spongiform encephalopathies