The DNA of a bacteria was isolated and it was determined that 15% of the DNA is composed of cytosine.What percentage of the DNA is adenine?
A) 15%
B) 30%
C) 35%
D) 70%

Question

Quizplus · Accepted Answer

In DNA, the percentage of adenine always equals the percentage of thymine and the percentage of cytosine always equals the percentage of guanine. Therefore, if 15% of the DNA is made up of cytosine, then the percentage of guanine is also 15%. That leaves 70% (100% - 15% - 15%) of the DNA to be composed of adenine and thymine, and since they are always equal to each other, adenine must make up 35% of the DNA.

The DNA of a Bacteria Was Isolated and It Was