Question

a double stranded dna strand contains 26 pyrimidines. how many purines will the copied strand contain? multiple choice 26 52 13 0

Explanation:

Step1: Recall Chargaff's rules

In a double - stranded DNA, the amount of purines (adenine + guanine) is equal to the amount of pyrimidines (thymine + cytosine). That is, A=T and G = C, so Purines = Pyrimidines.

Step2: Determine purine amount in copied strand

The copied strand of DNA will have the same base - pairing relationships as the original double - stranded DNA. If the original double - stranded DNA has 26 pyrimidines, the number of purines in the copied strand will be equal to the number of pyrimidines in the original double - stranded DNA due to complementary base - pairing during replication. So the number of purines in the copied strand is 26.

Answer:

A. 26