Scientists are thinking that the life on Earth appeared about 3.7-3.5 billion of years ago [1]. The first life forms wer

[answerhappygod]

Scientists Are Thinking That The Life On Earth Appeared About 3 7 3 5 Billion Of Years Ago 1 The First Life Forms Wer 1 (22.41 KiB) Viewed 15 times

Scientists are thinking that the life on Earth appeared about 3.7-3.5 billion of years ago [1]. The first life forms were very primitive single cell organisms. They established the molecular mechanisms to synthesize organic molecules that we are observing today common to all living organisms [2]. One of the characteristics of life is that all living things have DNA as a carrier of genetic information [2]. However, the scientists think that this was not always the case, the life begin using RNA as a genetic material and later switched to DNA [3]. What do you think, why this could be? Which processes that promotes preserving the genetic information and at the same time allowing for Genetic variation were made possible when Nature started to use DNA instead of RNA? Why it is so difficult, if not impossible, to acquire immunity against RNA viruses? Does it have something to do with the different nature of the viruses, or with the higher mutation rates in the RNA world?