A forensic scientist is trying to find out the number of adenine in the DNA sample that he obtained from a crime scene. What can he assume about the number of adenine? The number of adenine will be equal to the number of guanine. The number of adenine will be equal to the number of all the other bases. The number of adenine will be equal to the number of thymine. The number of adenine will be not equal to the number of any other base.
According to the complementary base pair rule, adenine is always paired with thymine (A and T are purine pairs), and cytosine with guanine (C and G are pyrimidines). The chemical structure of the bases make it so there are two hydrogen bonds between adenine and thymine, and three hydrogen bonds between cytosine and guanine.