Synthesis of proteins :
The DNA consists of the genetic code and directs protein synthesis by RNA. The two helix of DNA partly uncoils and approximately the individual strands are formed chains of RNA. The new chains comprise ribose in its place of deoxyribose and the base sequence is different which is computed by DNA, that is opposite every adenine of DNA, there finds on RNA a uracil; opposite guanine, opposite cytosine, cytosine; adenine, guanine, opposite thymine. So, AATCAGTT on DNA turns out to be UUAGUCAA on RNA.
One sort of RNA, called messenger RNA that takes a message to the ribosome, where protein synthesis really gets place. At the ribosome, messenger RNA starts a sequence of transport RNA molecules, each of which is overloaded with a specific amino acid. The order in which the transport RNA molecules are known as (-the sequence where the amino acids are arranged to form the protein chain) depends on the sequence of bases along the messenger RNA sequence chain. So GAU is the type for aspartic acid; phenyl alanine, UUU; valine, GUG. There are 64-three letter code words or codons.