General Virus Knowledge
Name a virus
Covid 19 / Influenza / Poliovirus / Tobacco mosaic virus / bacteriophage / pox viruses / herpes / measles / mumps / rubella / herpes (cold sores) / rabies / etc
True or false: All viruses have the same shape
false
True or false: Viruses can replicate by themselves
False! They require a live host to replicate
True or false: Viruses are used in the flower industry to produce new colour variations
True!
What are viruses?
Tiny, non-cellular structures
Name the 3 shapes of viruses that can be found.
Round
Rod-shaped
Complex
During the third stage of viral replication (synthesis), what is the virus using to make new virus parts?
The organelles of the host cell.
Give a medical disadvantage of viruses
They cause diseases / make living things sick
What specific type of apparatus can be used to view viruses?
Electron microscopes
Describe the structure of a virus
Outer protein coat (capsid) and a nucleic acid (either DNA or RNA but never both)
During the final stage of virus replication, the host cell bursts open. What is the name given to this process?
Lysis
Name one medical advantage of viruses
They can be used in genetic engineering as viruses are sometimes used to transfer genes from one organism to another. (or named example - eg to produce insulin for diabetics)
Bacteriophages may be used to control bacterial infections.
What type of parasite are viruses?
Obligate parasites
Why are viruses considered non-living?
Because they:
- Do not have cell organelles (eg ribosomes, mitochondria)
- Do not carry out any metabolic reactions on their own
Name and describe the stage of viral replication that happens after the synthesis stage.
4. Assembly -- The virus parts (i.e. the viral molecules that have been produced) are put together. New viruses are made inside the host cell.
Name one agricultural benefit of viruses
Viruses can be used as pest control or disease control in crops
Why can we not grow viruses on nutrient agar, like bacteria?
Because they require a host in order to replicate / they do not have their own organelles / energy to reproduce
Can antibiotics be used to treat viruses? Why / why not?
No - because viruses don't have any organelles / cell machinery for the antibiotics to damage
Name and describe the first two stages of viral replication.
1. Attachment: Virus attaches itself to the host cell. Proteins on the virus match up with receptor sites on the wall of the host cell
2. Entry: The virus forms a hole in the host cell. The viral DNA or RNA is injected into the bacteria
Name the virus responsible for cervical cancer
human papillomavirus (HPV)