1.5 Viruses and Subviral Particles Flashcards
What are the three parts of a virus?
- genetic information
- capsid
- fat capsule (optional)
What is the genetic information like for a virus?
- DNA
- RNA
- circular or linear
What is capsid?
Protein coating that is around the virus
What is the lipid envelope?
-optional piece on the virus that it supposed to protect it
What is the difference between a virus with a lipid envelope and one without?
- Lipid envelope is very easy to breakdown with heat or cleaning agents
- Without the lipid is actually a stronger virus
What VIRIONS?
-baby viruses that are made
What is a bacteriophage?
- virus infecting bacteria
- doesn’t go into the bacteria
- take some of the DNA of the bacteria with them for the next host
bacteriophage: Tail Sheath?
-injecting part that goes into the bacteria
bacteriophage: Tail fibers?
-receptors that identify the bacteria
RNA: Postive Sense?
- virus can just use the machinery from the host cell
- after they make the mRNA they can go to cytoplasm for the protein
RNA: Negative Sense?
- virus has to come in with its own parts
- RNA replicase
- complementary strand before it can go and make a protein
RNA: Retrovirus?
-RNA viruses that make themselves into DNA and then implant themselves into the genome of the host DNA
What is the viral cycle first step?
Infection virus is small enough to sneak or trick into the cell membrane or is invited in by the cell
What is the second step of the Viral Cycle?
using the parts
- depends on the type of virus
- retrovirus: use the nucleus for everything
- positive sense: nucleus to make the mRNA and then leaves for cytoplasm
- Negative sense: Has to come in with its own parts to make the mRNA before moving to the cytoplasm
What is step 3 in the viral life cycle?
leaving
- lysis: kill the host cell by popping it with babies
- extrusion: leave through the cell membrane
Lytic Cycle:
-When the virus is done creating the virions then it kills the host
Lysogenic Cycle:
- Prophage
- Keeps the host alive through integration of its genetic material
Can the lysogenic cycle turn into the lytic cycle?
-Under attack the cycle can change
Why might a bacteria keep on a lysogenic cycle?
-One on one virus to bacteria and keeps other viruses from effecting it
Prions:
- proteins that mishaps the cell
- proteins can not function properly
- very difficult for the cell to rid of them
Virons:
small pathogens found in plants
- silencers of the genome so the gene or protein never gets made
- HPD when exposed with HPB in humans that act silence the gene
