Viruses Flashcards
Dutch microbiologist _________________ named “virus” which means poison
BEIJERINCK
What are the four main parts to the virus?
CAPSID
DNA
BODY
FIBER
What is the capsid?
It’s the protein coat that surrounds the genetic material
What are the 3 main groupings of viruses?
BACTERIAL
ANIMAL
PLANT
Viruses do not display ____________________ characteristics
LIVING
Viruses cannot ___________________ independently
METABOLIZE
no respiration, protein synthesis, replication, etc…
Viruses must force infected ______________ __________ to replicate viral DNA
HOST CELLS
How do viruses reproduce?
They take over the cell’s transcription and translation to reproduce
What are the two types of viruses according to their effects on the host cell? (based on the type of reproduction)
LYTIC
LYSOGENIC
________________ viruses lyses (destroys) the host cell
LYTIC
_____________ viruses has a dormant stage
LYSOGENIC
What are the 5 steps in lytic viral reproduction? (lytic cycle)
ATTACHMENT PENETRATION REPLICATION ASSEMBLY RELEASE
In this stage of the lytic cycle, attachment to the host cell surface takes place.
ATTACHMENT
In this stage of the lytic cycle, the nucleic acid of the virus enters the cytoplasm of the host cell.
PENETRATION
In this stage of the lytic cycle, info on the viral nucleic acid directs the host cell to create new viral components.
REPLICATION
In this stage of the lytic cycle, components are put together.
ASSEMBLY
In this stage of the lytic cycle, enzymes from the virus destroy the host plasma membrane and release the new viruses
RELEASE
How long does it take to complete the lytic cycle?
20 minutes to an hour
Be able to draw out and diagram the lytic cycle.
YOU GOT THAT DUMBASS
What are the four steps to the lysogenic cycle?
ATTACHMENT
PENETRATION
INTEGRATION
REPLICATION
The lysogenic cycle usually _________________ the host
DOES NOT KILL
During what stage of the lysogenic cycle does the viral nucleic acid become part of the host cell DNA?
INTEGRATION
During what stage of the lysogenic cycle does the virus replicate?
REPLICATION (duh)
In the lysogenic cycle, how does the virus replicate?
It replicates when the cell itself replicates
___________________ may stay dormant or become lytic if conditions change. (x-rays, UV light)
THE LYSOGENIC CYCLE
What are the two types of human and animal viruses?
ATTACHMENT
PENETRATION
_________________ viruses don’t survive well outside a host
ANIMAL
Humans suffer from _________ to _________ viruses a year
2 to 6
What do plant cells have that stop viruses?
Thick Cell Walls
What must first happen to plants for viruses to get in?
The plants must first be damaged
How are viruses passed through plants?
They are passed on through seeds or a sexual propagation
What are viroids?
Short RNA strands with no protective coat
What causes plant diseases?
Viroids
___________ are smaller than viruses
Viroids
What are prions?
Prions are infective proteins that spontaneously arise
_____________ have no DNA or RNA
Prions
Prions cause what?
Prions cause transmissible spongiform encaphalopathies like BSE
What is BSE?
Bovine Spongiform Encephalitis
What is another name for Bovine Spongiform Encephalitis?
Mad Cow Disease
What is the transmissible spongiform encaphalapathy that occurs in sheep and goats called?
SCRAPIE
What is the transmissible spongiform encaphalopathy that occurs in elk and deer?
CHRONIC WASTING DISEASE
What is the transmissible spongiform encaphalopathy that occurs in humans called?
CJD
