Genetics of bacteria and their viruses

Ah I clicked on the wrong forum link. Oh well

Genetic recombination refers to the exchange of nucleotide sequences between two DNA molecules often mediated by segments that are composed of identical or nearly identical nucleotide sequences called homologous sequences. DNA molecules that contain new arrangements of nucleotide sequences are called recombinants. Since bacteria only have one chromosome, you need a second piece of DNA for crossing-over to take place in that bacterium. Without this foreign piece of DNA, there won't be any crossing-over. Think of homologous chromosomes in meiosis in eukaryotic cells and you'll get a good picture of what's happening.

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