Genetics of Viruses Flashcards
Virus
Small infection particle that consist of one or more nucleic acid molecule enclosed in a protein coat
Host Cell
A cell that is infected by a virus
Host Range
Number of different species & cell types they can infect (Ex. like only being able to infect lung cells)
All viruses have a protein coat called ________
Capsid
Caspid
Encloses a genome consisting of one or more types of protein subunits called capsomers
Viral Genome
Genetic Material in a virus where it can be either DNA or RNA
Virual reproductive cycle
Results in the production of new viruses
What are the steps for viral reproductive cycle?
- Attachment
- Entry
- Integration
- Synthesis of viral components
- Viral Assembly
- Release
Attachment
The virus attaches to the surface of the host cell (1st step)
Entry
After attachment the viral genome (either DNA or RNA) enters the host cell (2nd step)
Integration
Viruses contain an enzyme called integrase which cus the hosts chromsomal DNA & inserts the viral geneome (either RNA or DNA) into the chromosome (3rd step)
Prophage
When the chromosome DN is intergrated
Lysogenetic Cycle
The viral reproductive cycle when the phage DNA is a prophage
Reverse Transscriptase
An enzyme that can turn a viral RNA into DNA
Provirus
When a viral RNA is turn into viral DNA & the viral DNA is inserted into the host cell via integrate
Synthesis of viral compenents
The production of new virsues by a host cell involves the replication of the viral genome & the synthesis of virall proteins that make up the capsid
Viral Assembly
After all the necessary components have been synthesizedthey assembly into new viruses
Released
Last step where the new viruses are released
Latent Virus
An inactive virus
Lysogeny
Latency in bacteriophage
_____________ can cwitch betwen lysogenic & lytic cycle
Temperate phage
______________ can only follow the lytic cycle
Virulant phages
Episome
A genetic element that can replicate independently of the chromosomal DNA but can also integrate into chromsome DNA
