Non-Coding DNA

• In eukaryotes, much of the nuclear DNA does not code for polypeptides
• The genome within eukaryotic cells contains many non-coding sections of DNA

  • Non-coding DNA does not code for any amino acids
• Non-coding DNA can be found between genes, as non-coding multiple repeats

  • This means they contain the same base sequences repeated multiple times
• Within genes, only certain sequences code for amino acids

  • These coding sequences are called exons
• Within genes, only certain sequences code for amino acids

  • These coding sequences are called exons
  • Within the gene these exons are separated by further non-coding sequences called introns
• Exons - Regions of the gene which are coding

  • They contain the codons that are later read to make proteins
• Introns - Non-coding regions of the gene that do not contain codons needed to make the final protein

  • Introns are found between exons