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Text: There seems to be a large excess of DNA in the genomes of higher organisms. Long before it was possible to examine the nucleotide sequences of chromosomal DNA directly, it was evident that the relative amounts of DNA in the haploid genomes of different organisms has no systematic relationship to the complexity of the organism: human cells, for example, contain about 700 times more DNA than the bacterium E. coli, while some amphibian and plant cells contain 30 times more DNA than human cells. Each paragraph will be a test.

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