Flu vaccines need to be revised and changed every year because the flu virus constantly mutates. Flu viruses can change in two ways: drift or shift. Antigenic drift occurs when genes of the virus slowly change during replication until the immune system no longer recognizes it. On the other hand, antigenic shift occurs when a major change in the virus happens. This usually leads to a totally different kind of virus. This is what happened during the H1N1 scare in 2009.
DNA viruses like mumps are less prone to mutation due to the presence of DNA polymerase. RNA viruses are more prone to mutation because they undergo reverse transcription to simulate the role of DNA.
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The human impact on the Amazon rainforest has been grossly underestimated according to an international team of researchers. They found that selective logging and surface wildfires can result in an annual loss of 54 billion tons of carbon from the Brazilian Amazon, increasing greenhouse gas emissions.
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Both DNA and RNA
According to transcription we have DNA that will form MRNA
They are different because plasma is made up of groups of positively and negatively charged particles. However, gaseous electrons are bound to the nucleus.
