How viruses work
Everybody at some point catches a cold or the flu. Are bodies are more vulnerable to catching these during the flu and cold season. The flu and the cold are two of the commonest VIRUSES. Luckily they are not that harmful on our bodies, there are some viruses such as AIDS, hepatitis, Ebola hemorrhagic fever and acquired immunodeficiency syndrome which are far more serious and in some cases deadly. A virus can spread very easily in a school, in an office or even at home. Anywhere where there is a community of people viruses can be caught from each other. This diagram will show how a virus can spread within your own body.
This diagram shows what scientists call the LYTIC cycle. Regardless to the type of host cell, all viruses follow the lytic cycle. What the virus is doing is using the host cells chemical machinery enzymes to reproduce. The red spiral represents the virus genetic instructions and the orange part represents the protein coat around it.
The lytic cycle is the process in which viruses use the host cell.
- A virus attaches to the host cell
- The particle releases its genetic instructions into the host cell.
- The injected genetic material recruits the host cell’s enzymes.
- The enzymes make parts for more new virus particles.
- The new particles assemble the parts into new viruses.
- The new particles break free from the host cell.
The protein on the out side of the virus particle ” feels “ or ”recognises“ the proper host cell. This protein attaches its self to the membrane of the host cell. Some envelope viruses dissolve straight through the membrane of the host cell. This happens because both the virus envelope and the cell membrane are made of lipids. Once the virus is in the cell, the viral enzymes take over the host cells enzymes, making copies of the viral genetic instructions and new viral proteins using its genetic instructions and the cells chemical machinery. The copied genetic instructions and protein are combined to make replica viruses.
The new viruses then leave the host cell in one of two ways.
- Lysis-They break the host cell open destroying it.
- Budding- They pinch out from the cell membrane and break away with a piece of the membrane surrounding them. This is how envelope viruses leave the host cell. This way does not destroy the host cell.
The viruses can then keep going around the body and reproducing in another host cell. Viral infections can spread very quickly around the body.
Viruses can also use mitosis to help it reproduce this diagram shows how the viral genetic instructions can mix with the enzymes in the host cell, and be copied with them when the cell divides. The virus genetic instructions can then reproduce later, making more viruses. This cycle is called the ” LYSOGENIC “ cycle.
Viruses such as HIV and herpes go around the body in the lysogenic cycle rather than the lytic cycle.
When your body’s immune system responds to the infection, and whole fighting the infection, it produces” PYROGENS “. These are chemicals that cause your body temperature to increase. This slows down the rate in which the virus spreads as your body’s reactions work at their optimal at 37oC and when it rises above that, the rate starts to slow down.
Example viruses
This is what the HIV AIDS virus looks like. It stands for human immunodeficiency virus. It is a very complex virus, but nowhere as near as complicating as some viruses can get. It is an envelope virus and reproduces in the lysogenic cycle.
This is an image of hepatitis B. It is a naked virus as its outer coat is the protein (HBc)
These are all pictures of Ebola. As you can see it is a very weird shape compared to the other viruses. It is longs and skinny rather than circular. It is one of many hemorrhagic fevers and is often fatal. It gets it name from the democratic republic of Congo in Africa where it was first recognised. It is one of two RNA viruses in the Filovirdae virus family.
