Question

Two strands of a molecule of DNA are linked sidewise by

• A. all the above
• B. glycosidic bonds
• C. purine-pyrimidine hydrogen bonds
  
• D. ester bonds

Answer 1

The correct option is C purine-pyrimidine hydrogen bonds


Purine-pyrimidine hydrogen bonds

• The two DNA strands are joined together by complementary base pairing between the purines and pyrimidines.
• Adenine binds with thymine through two hydrogen bonds.
• On the other hand, guanine binds with cytosine through three hydrogen bonds.