Question

A primary transcript (immature, non-processed) single-stranded RNA molecule has the following nucleotide composition: 30% A, 20% G, 24% C, and 26% U. What is the nucleotide composition of the double-stranded DNA molecule from which it was transcribed?

Choose one:
A. 28% A, 22% G, 22% C, and 28% T
B. 20% A, 30% G, 26% C, and 24% T
C. 26% A, 24% G, 20% C, and 30% T
D. 30% A, 20% G, 24% C, and 26% T
E. 26% A, 24% G, 20% C, and 30% U

Answer 1

The nucleotide composition of the double-stranded DNA molecule from which the primary transcript was transcribed can be determined by pairing the complementary nucleotides. The nucleotide composition of the DNA molecule is 30% A, 20% G, 24% C, and 26% T.

Step-by-step explanation:

The nucleotide composition of the double-stranded DNA molecule from which the primary transcript was transcribed can be determined by pairing the complementary nucleotides. In DNA, adenine (A) pairs with thymine (T) and guanine (G) pairs with cytosine (C). Since the primary transcript contains 30% A, it must pair with 30% T in the DNA molecule. Similarly, 20% G pairs with 20% C, 24% C pairs with 24% G, and 26% U in the primary transcript pairs with 26% A in the DNA molecule. Therefore, the nucleotide composition of the double-stranded DNA molecule is 30% A, 20% G, 24% C, and 26% T.