A triplet codon is a specific sequence of three consecutive nucleotides that specifies or codes for a particular amino acid. A codon on the mRNA will specify the next amino acid added during the process of protein synthesis.
The standard genetic code is represented as a RNA codon table. The DNA codons in these tables occur on the sense DNA strand and are arranged in the 5' → 3' direction. A single amino acid can be coded by more than one codon as there are 61 triplet codons coding for 20 amino acids. This is called the degeneracy of the genetic code. Asparagine (Asn) is an alpha amino acid required for the development and the functioning of the brain. Asparagine is coded by the two triplet codons AAT and AAC.
It is estimated that the Precambrian Era lasted between 3.9 and 4 billion years. Many scientists believe that this era accounts for 90 percent of the world's history.
