Transcription of DNA Genes are not continuous segments of the DNA chain 1.A gene begins in an exon,a small section of DNA 2. Genes are interrupted by noncoding sections called introns 3. Genes take up again further down the chain in another exon The final mRNA molecule results after the noncoded sections are cut out and the remaining pieces are spliced together by spliceosomes 90%of human DNA seems to be made up of introns 10%of DNA contains coding instructionsGenes are not continuous segments of the DNA chain 1. A gene begins in an exon, a small section of DNA 2. Genes are interrupted by noncoding sections called introns 3. Genes take up again further down the chain in another exon The final mRNA molecule results after the noncoded sections are cut out and the remaining pieces are spliced together by spliceosomes ▪ 90% of human DNA seems to be made up of introns ▪ 10% of DNA contains coding instructions Transcription of DNA