Which of the following is MOST responsible for determining the structural stability of double-stranded DNA?
A) The attractive interaction between positively charged purines and negatively charged pyrimidines.
B) H-bonding between the OH of deoxyribose and purine and pyrimidine ring nitrogens.
C) Hydrophobic interaction between contiguous base pairs and hydrogen bonding between complementary bases on opposite strands.
D) Interaction between the phosphate groups in separate chains.
E) Hydrophilic interaction between the pentoses in separate chains.

Question

Quizplus · Accepted Answer

The hydrophobic interaction between contiguous base pairs (such as A-T and G-C) and hydrogen bonding between complementary bases on opposite strands are the main factors that determine the stability of double-stranded DNA. These interactions give the double helix its characteristic shape and prevent the two strands from separating. Additionally, the H-bonding between the OH of deoxyribose and purine and pyrimidine ring nitrogens also contributes to the stability of the double helix. The other options listed (A, D, and E) are not as central to the structural stability of double-stranded DNA.

Which of the Following Is MOST Responsible for Determining the Structural