91影视

DNA and RNA are nucleic acids. They are the storehouse of genetic information.

DNA is the genetic material in almost all organisms, except a few viruses. Some viruses thus contain RNA as the genetic material instead of DNA. DNA is known to be more stable than RNA.

The transition from an 鈥楻NA鈥� world to today鈥檚 DNA world could have happened with the aid of the reverse transcriptase enzyme. It is an enzyme that catalyzes the synthesis of DNA from RNA. The enzyme acts on the RNA template to produce a single-stranded DNA complementary to the RNA strand.

This enzyme then synthesizes another DNA strand complementary to the first DNA strand formed. Thus, double stranded DNA is obtained. As the RNA serves as the template for DNA synthesis by the reverse transcriptase enzyme, the genetic information in the RNA is passed into the DNA.

Today, the DNA acts as a template for RNA or mRNA synthesis almost in all prokaryotic and eukaryotic cells. During this process, the genetic information from DNA passes into mRNA. The mRNA then undergoes translation for protein synthesis.

However, in some viruses, RNA is the genetic material. In such viruses, DNA synthesis from RNA occurs with the help of the reverse transcriptase enzyme. Here, the genetic information flows from RNA to DNA and not otherwise.

Therefore, today, the flow of genetic information mainly occurs from DNA to RNA. However, the flow of genetic information from RNA to DNA happens in viruses such as HIV, with RNA as the genetic material.