An organism's genomic dna is analyzed and found to contain 22% thymine. what percentage of that organism's dna is guanine?

In an organism's genomic data, 100 percent is made up of adenine, cytosine, guanine and thymine. Adenine and thymine are complementary pairs in a DNA so they should have the same concentration in the DNA. This would also be the case for Cytosine and Guanine. We are given 22 percent of thymine so we also have 22% of adenine. This would leave us with only 100-22 = 78 percent for both guanine and cytosine. And since they are present in equal amounts, we simply divide the remaining percentage by two to determine the amount of each. Therefore, there would be 78 / 2 = 39 percent of guanine present in that certain DNA. 

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