By Emma Wilson
Characteristics of Viruses
- They are considered both a living and non-living things
- They are enclosed in a protective envelope
- They have spikes, that help them attach to the host cell (which is a living cell in which virus' multiply.)
- They are non-cellular
- They have a nucleic acid core containing DNA and RNA
- There ribosomes and enzymes are absent, which are needed for metabolism
- They contain a protein coat called capsid
Shape and Cell wall
- In the Influenza virus they are polyhedral shapes
- In the Ebola virus they are helical in shape
- In the bacteriophage they are cylinder in shape
- The viruses cell wall is the capsid.
Movement and How they obtain energy
- There are two types of movement with viruses
- The first one is slow, local movement which they do when they move to one cell to another
- The second one is fast, systemic movement
- Viruses can't make their own energy so they rely on the energy within the cell they are in. They can't do anything if they are not in a living cell.
- The viruses reproduce by latching onto the host cell. They inject their genetic material into the host cell. The host uses the material to create new viruses.
How are viruses harmful and helpful
Viruses can be harmful but they also can be helpful. They can be modified to be used to introduce DNA and RNA. People can use the DNA and RNA to create proteins which the body needs to help fix a problem. They can be harmful by causing disease. Viruses also have a role in some cancers too.
Why are viruses harmful
The retrovirus is a virus that puts its own viral DNA in the host cell's DNA. This allows the viral DNA to keep on making copies of itself taking advantage of the host cell functions.
This viruses causes HIV,influenza,and hepatitis. The virus will always stay with the host cell
History of viruses
- There was a flu pandemic in 1918.
- It infected 500 million people all over the world.
- It killed about 50 to 100 million people.
- Flu usually kills children and elderly or sickly people.
- There was also the Black Death in 1347 in Europe.
- There are so many deadly viruses and some still haven't been found.
- Viral infections are hard to treat because the viruses live in your body's cells. Antibiotics do not work for viruses. The doctor usually give you medicine to stop the symptoms.
- There are a million viruses per milliliter of sea water
- The name virus came from a Latin word meaning slimy liquid or poison
- Walter Reed found the first virus, yellow fever virus in 1901
- Viruses are not alive; they are a complex organic matter
- Viruses are not dead either, they have genes, they reproduce,etc.
- Viruses can infect other viruses
- Without viruses we not be alive. They created the first cell which became what we are today.
Viruses: Virus Replication and The Mysterious Common Cold