The Genetic Code
Genetic code
- DNA molecules carry the genetic code as a sequence of nitrogenous bases in the nucleotides
- These bases are adenine, guanine, cytosine and thymine
- One of the strands of a DNA molecule will carry the base sequence that will be read by enzymes
- This strand is known as the coding strand
- The sequence of bases that form genes on the coding strand will determine the order of amino acids in the proteins that are synthesised
- The code is read as a triplet of bases, called a codon, with each sequence of three bases coding for one amino acid
- Remember that there are 20 different amino acids that could be coded for
- The sequence of amino acids will determine the shape and function of the protein that is synthesised from the code
From gene to protein diagram
The sequence of DNA bases in the genes codes for the production of a specific protein molecule