DNA structure Transitional Reasoning Practice

Questions

1. 1.

   A molecular genetics team synthesizes two distinct double-stranded DNA fragments, Fragment 1 and Fragment 2, each measuring 400 base pairs in total length. Quantitative analysis reveals that adenine accounts for 15% of the total nitrogenous bases in Fragment 1, whereas adenine accounts for 35% of the total nitrogenous bases in Fragment 2. Based on the structural properties of double-stranded DNA, which of the following comparisons between these two fragments is correct?

   • A) Fragment 2 contains a greater total number of purine bases than Fragment 1 because of its higher adenine concentration.
   • B) Fragment 1 requires a higher denaturation temperature than Fragment 2 because it possesses 160 more hydrogen bonds between complementary strands.
   • C) Fragment 1 has fewer covalent phosphodiester bonds along its sugar-phosphate backbone than Fragment 2.
   • D) Fragment 2 requires more thermal energy to separate into single strands because adenine-thymine base pairs share three hydrogen bonds.

Answers and step-by-step solutions appear after you finish the test.