Final answer:
The genetic code is a system that translates each triplet codon in mRNA into an amino acid for protein synthesis. There are 64 possible codon combinations, allowing more than one codon per amino acid, making the code degenerate but efficient for protein assembly.
Step-by-step explanation:
The genetic code is an essential feature of all living organisms, defining the correspondence between the sequence of nucleotide triplets, known as codons, in mRNA and the sequence of amino acids in a protein. Each codon consists of three nucleotides and is read in a 5' to 3' direction from the mRNA. This three-nucleotide code allows for 64 possible combinations (4³), which exceeds the number of amino acids, thus making the genetic code degenerate; some amino acids are specified by more than one codon. The significance of this coding is that it directs the ribosomes in the cytoplasm to assemble proteins with the correct sequence of amino acids, reflecting the instructions originally encoded in the DNA.