Virology Flashcards
what viruses have a lytic life cycle
(cause the cell to explode)
T3, T7 and T2, T4
(double stranded)
what viruses are temperate (integrate their genomes into a host chromosome)
Mu and lambda
(double stranded)
what is a lysogenic cell?
a bacterial cell which can produce and transfer the ability to produce a phage
what is a prophage?
A prophage is a bacteriophage genome that is integrated into the circular bacterial chromosome
what is transduction?
the process by which a virus transfers genetic material from one bacterium to another
what happens during the eclipse period of viral reproduction?
causing infection and the appearance of new mature virus in a host cell
what are plaques on agar
zones of lysis
where does the T1 virus attach
iron transport protein
what type of viral life cycle occurs when viruses lyse host cells after infection
virulent mode
what type of viral life cycle occurs when viruses replicate their genomes in tandem with the host genome and without killing the host
temperate mode
(viruses can also be lytic)
The time elapsed between successful cell infection and the start of virus production in the cell is called what?
the eclipse period
The period that is the time taken by a phage particle to reproduce inside an infected host cell is called what?
the latent period
what bacteriophage is used as a cloning and dna sequencing vector in genetic engineering
bacteriophage M13
- does not lyse the cell
where does lamda virus attach itself on a cell (can be used in genetic engineering)
specific site on the chromosome
where does mu attach itself on the cell (can be used in genetic engineering)
generalized attachment to the cell (anywhere)
mu: mutation
can temperate viruses kill the host cell?
yes through lytic cycle
what is the lysogeny state of a virus?
state where most of the virus gene is not expressed and virus genome (prophage) is replicated in synchrony with host cchromosome
what is a lysogen
a bacterium containing a prophage
what are cos sites
sticky ends on lambda virus
what are the twoo repressor prooteins that control the regulation of lytic vs lysogenic events in lambda
- cl protein: causes repression of lambda lytic events
- cro repressor: controls activation of lytic events
how does the virus use the cell to protect it’s dna?
by using 5-hydroxymethyl-cytosine which endonucleases cant recognize
what is a nucleocapsid
the capsid of a virus with the enclosed nucleic acid.
picture of a nonenveloped polyhedral virus
picure oof morphology of an envelope heliccal virus
