CH6 Flashcards
what is a virus called when it integrates itself inside a bacteria genome?
a prophage (provirus)
what is a reverse transcriptase
Enzyme that copies RNA to DNA
video: https://www.youtube.com/watch?v=v9EL8V-6la4
what is the role of capsomers
the units used to construct the capsid
what is the layer between the envelope and capsid
the tegument proteins
most plant viruses have what kind of viral symmetry
helical
mimiviruses are infected by smaller viruses called what?
virophages
little viruses that infect other bigger viruses is called what
sputnik
what are the five ways viruses are classified
- genome composition
- capsid symmetry
- envelope
- the size of virion
- host range
if a virus infects the lungs it is called what
pneumotropic
if a virus infects the skin it is called what
dermatropic
if a virus infects the neurons it is called what
neurotropic
what are the seven classes in virus classification
class I: Double-stranded DNA viruses
class II: Single-stranded DNA viruses
class III: Double-stranded RNA viruses
class IV: (+) single-stranded RNA viruses
class V: (–) single-stranded RNA viruses
class VI: RNA retroviruses (needs reverse transcriptase)
class VII: DNA pararetroviruses (the reverse transcriptase is not part of the virus)
what class of viruses requires a plant host reverse transcriptase to make dsDNA
class 7 DNA pararetroviruses
class that requires rna dependent rna polymerase to make mRNA and replicate its genome
class 5 (–) single-stranded RNA viruses
class that requires rna-dependent rna polymerase to make a template for mRNA and genome replication
class 4 (+) single-stranded RNA viruses
class that packages its own reverse transcriptase to make dsDNA
class 6: RNA retroviruses (needs reverse transcriptase)
class that uses its own or host dna polymerase for replication
class 1: Double-stranded DNA viruses
class that requires rna-dependent rna polymerase to make mRNA and genomic rna
class 3: Double-stranded RNA viruses
class that requires RNA polymerase to generate a complementary strand
class 2: Single-stranded DNA viruses
cheat sheet slides
slides 34-36
three forms of defense against viral infection within bacteria
- Genetic resistance
- Altered receptor proteins - Restriction endonucleases
- Cleave viral DNA lacking methylation - CRISPR integration of phage DNA sequences (Clustered regularly interspaced short palindromic repeats)
- A bacterial immune system of sorts
rhinovirus binds to what cell receptor
ICAM
image on how viruses enter the cell
for DNA replication to occur the cell needs to be in what phase so that the virus can have successful replication
the S phase because that is when DNA polymerase is present
how do DNA viruses replicate
Can utilize the host replication machinery
how do RNA viruses replicate
Use an RNA-dependent RNA-polymerase to transcribe their mRNA
how do retroviruses replicate
Use a reverse transcriptase to copy their genomic sequence into DNA for insertion in the host chromosome
two ways the progeny of viruses are released from the host cell
- lysis of the cell
- budding: All enveloped viruses bud from a membrane.
what is the P53 gene
tumor suppressing gene
three ways viruses can infect a plant
- Contact with damaged tissues
- Transmission by an animal vector
- Transmission through seed
viruses are transmitted to uninfected cells by what mechanism
the plasmodesmata
