Question

1. what are the two purines? what are the two pyrimidines?

Explanation:

Purines and pyrimidines are nitrogen - containing bases in nucleic acids. Purines have a double - ring structure. Adenine (A) and guanine (G) are the two purines. Pyrimidines have a single - ring structure. Cytosine (C) and thymine (T) (in DNA) or uracil (U) (in RNA) are pyrimidines. Since the question does not specify DNA or RNA, if we consider the most common case (DNA), the two pyrimidines are cytosine and thymine.

Answer:

The two purines are adenine and guanine. The two pyrimidines are cytosine and thymine.