virology Flashcards
are viruses cellular?
no
Do viruses leave fossil records?
no
how long have viruses been around?
as long as the cells the infect
who attempted Kosch postulates on tobacco leaf infections and tried to grow it on media-filtrate infection
Ivanovsky
all viruses must be:
1.small in size
2.obligate intracellular parasites
3.capsid
4.genome-inside capsid (made of nucleic acid)
-segmentede or non
5.few genes
6.no metabolism
7. some have an envelope (influenza)
8.host range
what is a viroid?
a piece of nucleic acid that are able to infect cells (hepatitis infections)
what is a prion?
proteins that are infectious (protenatious infectious agent) EX: chronic wasting disease, mad cow disease
what is a capsid?
a protein shell typically made up of 1-2 types of proteins in 100,000’s of copies that form a shell
what is a capsid shape referred to as?
capsomere
what are the types of capsid categories?
-polyhedral virus (spherical)
-helical virus (rod shaped)
-complex virus, stalk covered in sheath, tall fiber and bas plate pins (all other viruses)
what is a nucleocapsid?
term for the nucleic acid within a capsid
what do virus genomes consist of?
DNA or RNA, single or double stranded
what are the combinations of virus genomes?
4 combos
-dsDNA -ssDNA -dsRNA -ssRNA
what is the calcification of viruses called?
Baltimore Classification
what is the class 1 in Baltmore Classification?
dsDNA
what is the class 2 in Baltmore Classification?
ssDNA
what is the class 3 in Baltmore Classification?
dsRNA
what is the class 4 in Baltmore Classification?
(plus sense) +RNA
what is the class 5 in Baltmore Classification?
(minus sense) -RNA