Chapter 20, Problem 20.68QP

Interpretation Introduction

Interpretation:

The possibility of several alternative mRNA sequences that could encode the same peptide has to be explained.

Concept Introduction:

Since one triplet of nucleotides constitute one codon and there are 4 nucleotides only, so the number of triplets is calculated as follows:

  $\begin{array}{c}\text{Number of triplet}=4^3\\ =64\text{ triplets}\end{array}$

Since there are only 20 amino acids, therefore many of these triplets code for more than one amino acid. In total, there are 64 codons that constitute the genetic code.