Flashcards in Viral Structure, Replication and Pathogensis Deck (65)
What are the classifications of viruses?
What is virology?
Scientific study of viruses and disease they cause
What is a virus?
Infective agent typically consisting of a of a nucleic acid in a a protein coat
Obligate intracellular parasite that depends on the host for reproduction
How are viruses similar to living organisms?
Proteins and glycoproteins
How are viruses different from living organism?
No polysaccharides, small molecules or ions
If they are lipid they are only enveloped
Do antibiotics work against viruses?
Does a virus contain DNA and RNA?
No they can only have DNA or RNA, never both
What are possible structures for DNA viruses?
Single or double strand
Linear or circular
Open or closed
Continuous or nicked
What are some possible structure for RNA viruses?
Single or double strand
Single strand may be plus or minus sense
What are the steps to name a virus?
1. Structure: size morphology and nucleic acid
2. Biochemical characteristics: structure and mode of replication
4. Means of transmission:
5. Cell, tissue or organ
6. Host cell range
What a virion?
Structurally complete infective virus particle
What is a capsid and what are capsomeres?
A protein shell that encloses the nucleic acid
Capsomeres are units on the surface in clusters
What is a nucleocapsid?
Capsid along with the inside nucleic acid
What is the tegument of a virus?
Proteinaceous material between envelope and capsid
If a virus is said to have an icosahedral shape, what does it look like?
Rigid and uniform structure
ex. Multiside hexagon
If a virus is said to have a helical shape, what does it look like?
A naked virus...
Protects viral genes from inactivation by adverse environments
Packaged, protect and deliver genome
Mediate attachment (VAP)
Release by cell lysis
An enveloped virus...
Has a lipid bilayer with embed proteins
More susceptible to chemical agents
Determines host cell specificity and penetration
Released by budding
A virus is icosahedral naked. What types of genome does it have?
dsDNA, ssDNA, dsRNA, ssRNA
A virus with an icosahedral shape and is enveloped has what types of genome?
dsDNA, dsRNA, ssRNA
A virus has a helical shape and is naked. What are its genomes?
dsDNA, ssDNA, ssRNA
An enveloped helical virus is found. What genome will it have?
What are the 2 types of exceptions to viral symmetry?
Complex viruses: poxvirus and bacteriophages
What is tropism?
Factors that affect host range
What are some factors that allow viruses to enter cells?
Can use more than one receptor or many viruses use the same receptor
What are the most common routes of entry for a virus?
Blood and bodily fluids
What are some viruses that enter through blood or fluid?
CMV, EBV, HBV, HCV, HIV
If an insect bites you, what viruses could it transmit?
Dengue, EEEV, WEEV, West Nile
Oh no! You touched a surface covered in viruses! What could viruses could you get?
HSV, smallpox, VZV