Question

One of the questions early geneticists had to answer was how only four nucleotides can specify placement of 20 amino acids in proteins. Today we know that ________, a sequence of three adjacent nucleotides, determine the insertion of a specific amino acid in a polypeptide chain.

Answer 1

Codon

Explanation:

The sequence of DNA is transcribed into mRNA, containing the sequence for protein synthesis, protein is synthesized according to the codons in mRNA. This sequence of nucleotide on DNA/ RNA is divided into a series of three nucleotide units, and one unit of three nucleotide is known as codons.

There are overall 64 codons, 61 codons out of 64 codons, codes for overall 20 amino acids, and the remaining three are stop codons.

These there codon do not code for any amino acid.

And these 61 codons, they code for total 20 amino acids. So one amino acid can be coded by one or more than one codons.