Chap 13- Animal Viruses Flashcards
(33 cards)
Bacteriophages and animal viruses have similar mechanisms of attachments to host cells,
both have appendages to attach to receptors on host cell’s plasma membrane. (animal viruses have spikes)
Multiplication of Animal Virus (APUBMR)
ATTACHMENT- viral N.A attaches to host cell wall, PENETRATE- virus entire nucleocapsid enters host cell via endocytosis or fusion; UNCOATING- protein separates from N.A in virion pre replication; Biosynthesis- production of N.A & proteins; MATURATION- components (DNA & proteins from cytoplasm in nucleus) assemble RELEASE- by budding (enveloped) or burst/rupture
In animal viruses, penetration mechanism into host cell depends on?
Whether virion is enveloped or non enveloped
NAKED, NON ENVELOPED virions enter host cell via ______
Endocytosis- host cell membranes cave in forming vesicle that surrounds virion
ENVELOPED virions enters host cells via ______
fusion with host membrane (virion envelope fuses to host cell membrane)
Attachment sites on virions ______? Attachment sites on host cell plasma membranes _____?
Spike; Receptor Sites
process where release of nucleic acid from capsids(proteins) done prior to replication; carried out by enzymes
uncoating
Virus Replication Process is aka
Biosynthesis
How does viral DNA get to make copies of themselves?
They force host eukaryotic cells into S phase of mitosis
occurs during interphase, and is responsible for replication of DNA
S-phase
Animal viruses can either be __________ , while bacteriophages can only be _______ ?
RNA OR DNA; DNA ONLY
How many strands does Animal Virus DNA have?
It can either have Single strand of DNA or Double strand of DNA (replication usually happens in nucleus)
Animal Viruses- Replication of DNA takes place ______? Biosynthesis of proteins take place _____?
nucleus; cytoplasm
process where completed DNA virion is transported from nucleus to cell membrane for it to EXIT via budding or lysis
RELEASE (animal virus DNA rep)
WHat forms do RNA virus come in?
SINGLE STRANDED or DOUBKE STRANDED
SINGLE STRANDED RNA can present in 2 forms;
SENSE STRAND- (+)RNA or ANTISENSE STRAND (-)RNA
this strand acts as mRNA
(+)RNA sense strand
this strand acts as template for (+)RNA
(-)RNA antisense strand
RNA replication is only done by ______?
viruses
Where does biosynthesis and maturation occur during RNA replication?
Cytoplasm
RNA viruses that use their viral RNA as a template for DNA “reverse transcription”
retrovirus (process carried out by reverse transcriptase)
viral DNA created from viral RNA gets incorporated into host chromosome and becomes a ______
provirus
the virus never comes out of chromose and is protected from host’s immune system
provirus
infection w/ rapid onset; short duration; immune system gradually eliminates virus
ACUTE infection
