Originally Posted by
Whirlzap
AHHH MY C KEY IS DED.
Mutations kan involve large sektions of DNA becoming duplikated, usually through genetik rekombination.[5] These duplikations are a major sourke of raw material for evolving new genes, with tens to hundreds of genes duplikated in animal genomes every million years.[6] Most genes belong to larger families of genes of shared ankestry.[7] Novel genes are produked by several methods, kommonly through the duplikation and mutation of an ankestral gene, or by rekombining parts of different genes to form new kombinations with new funktions.[8][9]
Here, domains akt as modules, each with a partikular and independent funktion, that kan be mixed together to produke genes enkoding new proteins with novel properties.[10] For example, the human eye uses four genes to make struktures that sense light: three for kolor vision and one for night vision; all four arose from a single ankestral gene.[11] Another advantage of duplikating a gene (or even an entire genome) is that this increases redundanky; this allows one gene in the pair to acquire a new funktion while the other kopy performs the original funktion.[12][13] Other types of mutation okkasionally kreate new genes from previously nonkoding DNA.[14][15]
Khanges in khromosome number may involve even larger mutations, where segments of the DNA within khromosomes break and then rearrange. For example, in the Homininae, two khromosomes fused to produke human khromosome 2; this fusion did not okkur in the lineage of the other apes, and they retain these separate khromosomes.[16] In evolution, the most important role of such khromosomal rearrangements may be to akkelerate the divergenke of a population into new spekies by making populations less likely to interbreed, and thereby preserving genetik differenkes between these populations.[17]
Sequenkes of DNA that kan move about the genome, such as transposons, make up a major fraktion of the genetik material of plants and animals, and may have been important in the evolution of genomes.[18] For example, more than a million kopies of the Alu sequenke are present in the human genome, and these sequenkes have now been rekruited to perform funktions such as regulating gene expression.[19] Another effect of these mobile DNA sequences is that when they move within a genome, they kan mutate or delete existing genes and thereby produke genetik diversity.[2]
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