Viruses Flashcards
The two common types of DNA viruses are…
Phage T4 (virulent) & Lambda (temperate)
Virulent phage follow a _________ pathway, resulting in the ________ of the cell.
lytic; lysing
Temperate phage can follow either a _________ pathway or a _________ pathway (which results in a period of ___________)
lytic; lysogenic; dormancy
Resources plentiful: ________
Resources scarce: _________
lytic; lysogenic
Cells affected by phage in lysogeny that were permanently altered and are now life threatening diseases:
- Scarlett fever
- Diphtheria
- Botulism
A phage in lysogeny is sometimes called a …
Prophage
DNA polymerases…
make DNA
RNA polymerases…..
(with primase) make RNA
What RNA viruses need which is either brought along with them or immediately synthesized:
Replicase/Viral RNA Pol/Viral Replicase which is an RNA dependent RNA synthesizing enzyme
Three main flavors of RNA viruses
- (+) sense strand
- (-) sense strand
- Retroviruses
Nucleid acid synthesis, whether in the living or viral world, produced an ________________,_____________ molecule.
antiparallel, complementary
Components of HIV
Viral protein, protease, integrase, receptor-binding glyctproteins, viral RNA, reverse transcriptase
Reverse transcriptase
- RNA-dependent, DNA-synthesizing enzyme
- Degrades RNA component of RNA-DNA hybrid
- DNA-dependent, DNA-synthesizing enzyme (?)
HIV has very limited range of host cell specificity…
…host cell must display CD4 molecule and have a co-receptor (chemokine family)
Example of cells that display CD4 molecule and co-receptor
T-cells in our immune system
