Exam 1 Flashcards
(46 cards)
Virus Definition
infectious, obligate, intracellualr parasite
composed of DNA or RNA, a protein coat, and sometimes an envelope of host plasma membrane
CThTV is a …
virus that promotes thermal tolerance in plants
How does CThTV promote thermal tolerance in plants
promotes fungal growth on the plant
CThTV stands for
Curvularia thermal tolerance virus
4 main characteristics of most viruses
- smaller than bacteria
- dependent upon the host cell to reproduce
- genome composed of only DNA or RNA
- receptor binding proteins to attach to host cell receptors
MiMi virus stands for
Mimicking Microbe
infects amoebas, 1 million bp genome
Pandora virus
larger than mimi virus, infects amoebas
viruses infect ___________
all living things
aquatic viromes are ________ because
essential for nutrient cycling, they free up organic matter for use by new life
viruses out number cellular life by —-
10 to 1
2 main qualities of ALL viruses
- obligate molecular parasites
2. must make mRNA to be used in cellular machinery
Bacteriophage therapy
weapon against superbugs, can also be used in the treatment of biofilms
Gene therapy
used to deliver functional copies of non-functional genes via retroviruses adenoviruses
Vaccine development
beneficial use of viruses
Virotherapy
oncolytic viruses used to kill cancer
Viral life-cycle (5) stages
- virus
- resevour (source of virus)
- transmission to suseptable host
- portal of entry into this host
- portal out of host
2 means of disease transmission
- direct
2. indirect
direct disease transmission
touching kissing animal bite sneezing breast milk sex coughing
Indirect disease transmission
water insects aerosols food fomites blood
Why do virus particles form (5)
- Protection - of nucleic acid from the immune system and chemical degradation by nucleases
- Recognition - outer surface is involved in recognition of and interaction with the host cell
- Self-assembly - simplest protein coats can form spontaneously, using little energy to assembly and possessing great stability
- Fidelity - proteins coded for by viruses are small, and therefore reduce the chances for error during expression
- Economy - Icosahedron is close to being a sphere, most volume least surface area, uses same protein over and over again
3 types of viral shapes
- Icosahedral, 20 identical triangular faces
- helical, shaped like cylinder
- complex, less common
Baltimore classification system is based on….(4)
type of nucleic acid
ds or ss
polarity
presence of reverse transriptase
Baltimore has — classes
7
all viruses must somehow generate —-
positive sense ssRNA
