The Spread of Viruses
DNA
DNA in viruses help them spread by replacing the DNA of the host cell. Since viruses don't have all the parts of a cell and can't reproduce on their own, they depend on other cells to reproduce for them. The viruses target and attach themselves to other cells, then inject their DNA into them. The DNA is taken in and replaces the existing DNA in the nucleus of the cell. This causes the nucleus to order the ribosomes to create new copies of the virus based off of the DNA injected into the cell. The cell keeps producing these copies until they break down the plasma membrane of the cell and burst out to find more cells to infect.
|
RNA
Some viruses, like the flu virus, only use RNA to spread. Much like DNA viruses, the RNA virus finds a host cell and inserts its RNA into the cell. This new RNA replaces the existing nucleic acid. However, unlike DNA viruses, the RNA is directly read by the ribosomes, which create new copies of the virus. These copies will also burst from the cell once enough are produced. The new viruses will find new cells to infect and produce even more viruses.
|