Question

when examining many bacterial genomes, it has been observed that the relative abundance of open reading frames (ORFs or genes) associated with DNA replication rapidly decreases as genome size (or the number of ORFs) increases. Provide an explanation for this observation.

Answer 1

As the genome size longer the no. Of open reading frame keep on decreasing or increasing less in no. Or % compared to increase in genome length. The main reason is that as the length of genome increased the chances of getting exposed with UV or mutagen increases and that could leads to mutation in open reading frame and this mutation could pass to next generation. So to overcome this challenge, nature as increases the no. Of junk DNA more as the size of genome increaes so that if genomic DNA get expose of UV than chances are there that mutation occur in junk DNA not in coding sequence hence these mutation does not code any protein so no changes observed in organism or nex regeneration.

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