The lysis of bacteria growing on an agar plate produces clearing in the lawn of bacteria. These clearing are called plaques.
define plaque forming unit (PFU)
Since one infectious particle is responsible for one visible plaque, each particle is considered to be a plaque forming unit.
define host
the cell the bacteria infects
define T4 phage
bacteriophage that looks like a spaceship
DNA is packaged in the head and the tailhelps with the infection process
what is a nucleic acid?
They carry the genetic information in all cells.
Which types of nucleic acid may viruses contain?
Viruses carry either RNA or DNA but never both. They are designated as either RNA or DNA viruses.
Can a virus contain more than one type of nucleic acid?
No. It is either an RNA or a DNA virus, but never both.
What are the 5 steps of the T4 phage life cycle?
adsorption
penetration
replication
assembly
release
What is the adsorption phase?
tail fibers of the phage bind to the host's cell wall (attachment)
What is the penetration phase?
The enzymes present in the phage tail degrade the host cell wall and the viral nucleic acid passes through the hollow core into the host cel's cytoplasm.
What is the replication phase?
the phage genome uses the cell's synthetic machinery for production of new phage components.
What is the assembly phase?
the phage components are assembled into mature virulent phage particles
What is the release phase?
enzymes lyse the host cell wall and allow the viruses to escape from the host
What is the host of the T4 bacteriophage?
E. coli
Which component of the T4 bacteriophage contains its nucleic acid?
DNA is packaged in the head
What is the purpose of 5 tryptone agar plates?
They are used to plate the dilution tubes
What is the purpose of eight 9-mL tryptone broths?
They are used for the dilution process
What is the purpose of the broth culture of E. coli?
The E. coli is the host for the T4 bacteriophage
What is the purpose of the sterile 1 mL pipettes?
A sterile pipette must be used each time to accurately transfer the broth and not cross contaminate