lecture 1 and 2 Flashcards
What does it mean to be an obligate intracellular parasite?
inert outside of host, require host replication machines to replicate
How and Why do viruses adapt
Viruses adapt and evolve via mutations to better infect other host
What is a transient virus
a virus that does not cause disease
what is a persistent virus
a virus that never clears, stays in body forever
how much of the human genome is due to retrovirus mutation
8% at least
How was the first virus seen
Via electron microscope that diffracts light
What were the first distinguishable things between a virus and bacteria?
Viruses are filterable and cannot grow in broth or sap
Where can virus names be derived from (7 things)
anatomical site, disease association, isolation place, person who discovered it, biochemical attributes, infected cell attributes, disease symptoms
How do we classify viruses?
order, family, genus, species
What is a strain?
a virus with slightly different genomic sequences
what is a serotype
viruses with different antibiotic response
what is a quasi species
many minor mutations that build up in one person
What are capsomeres and protomers
capsomers are the units that make up a protein capsid, promoters are the individual units that make up capsomeres
What advantage do enveloped viruses have?
can evade some immune responses
What are the components of an enveloped virus?
nucleocapsid, matrix proteins that anchor the envelope to the capsid, and glycoproteins that can act as viral attachment proteins to allow viral entry
How is the genome organized, what are its possible characteristics
RNA or DNA, circular or linear, single or segmented, one copy or two (RV)
What are the relative genome sizes of living organisms
virus is smallest, then bacteria, fungi and plant mammal cells
What are the Baltimore viruses
ssDNA, dsDNA, (+)ssRNA, (-)ssRNA, RNA RV, DNA RV
How do viruses overcome the one gene, one protein
stuttering to change the reading frame, making large polypropdteins that clip the mRNA into smaller proteins,
utilizing multiple start sites to make different proteins, using multiple splice variants
