There are four different nitrogen bases, adenine, thymine, cytosine and guanine. The synthesis of a particular protein such as insulin is determined by the sequence in which these bases are repeated (see fig.
Sixty three nucleotides are required for synthesising the A chain and ninety for the B chain, plus a codon at the end of each chain,signalling the termination of protein synthesis.
Hair grows from your head, nonstop, day in and day out. The cells of your hair follicles somehow generate all of the protein that make up this hair. How is this protein created? The answers to these questions are DNA replication and protein synthesis. The activity in this section places you within the cell, involving you with the processes of DNA replication and protein synthesis.