Mix DNA with complementary RNA and heat to separate DNA strands

^ Cool the mixture Complementary sequences pair.

DNA may reanneal with its complementary strand...

DNA may reanneal with its complementary strand...

Conclusion: Coding sequences in a gene may be interrupted by noncoding sequences. >---'

A 14.2 The noncolinearity of eukaryotic genes was discovered by hybridizing DNA and mRNA. (Electromi-crograph from O.L. Miller, B.R. Beatty, D.W. Fawcett/Visuals Unlimited.)

introns were thought to be entirely absent from prokaryotic genomes, but they have now been observed in archaea, bac-teriophages, and even some eubacteria. Introns are present in mitochondrial and chloroplast genes, as well as nuclear genes. In eukaryotic genomes, the size and number of introns appear to be directly related to increasing organismal complexity. Yeast genes contain only a few short introns; Drosophila introns are longer and more numerous; and most vertebrate genes are interrupted by long introns. All

Ovalbumin gene

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