The early earth was a very hostile environment, essentially beginning around 4.6 billion years ago. Some of the earliest known rock can be dated back to this time. Skip ahead about .8 billion years and the first prokaryotes, the bacteria and archea, were beginning a long journey that would mark the beginning of life on planet earth. But we ask ourselves, how did this all begin; what is the fundamental necessary components of life, when and how did this happen? Scientists have put together a strong idea of how this happened. Cells need 4 basic things to be considered alive, a membrane structure, genetic material, the ability to replicate this material, and a metabolism. We have solved 3 out of the four basic needs and can call this “cell” a protocell. The membrane of a protocell consists of fatty acids and is very stable, the genetic material is RNA and replication takes place one of two ways; with heat that denatures the RNA or with an enzyme called a ribozyme. The atmospheric conditions on the early Earth may have played an important role in the formation of components of nucleic acids that make up genetic material, including the sugar ribose and the four nucleobases. Scientists have shown that clays such as montmorillonite are able to catalyze polymers of RNA from single nucleotides. These clays could have existed on beaches and also at the bottom of the ocean near hydrothermal vents. Montrmorillonite can also catalyze fatty acid vesicles. When a high concentration of RNA nucleotidess are absorbed onto montmorillonite, the nucleotides closest to each other react and form a single strand of RNA. RNA is able to replicate itself in a non-enzymatic manner. Single nucleotides can find their base on a template strand of RNA. When heat is applied the two strands of RNA are separated into two identical strands. Heat comes from many sources. In the shallow ocean, RNA near the surface is denatured by ultra violet radiation during the day where it uncoils...
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