Which molecule contains ribose?

Which molecule contains ribose?

• A. DNA
• B. RNA
• C. Both DNA and RNA
• D. Neither

Answer: (B)

The sugar component distinguishes the two nucleic acids. RNA uses ribose as its five-carbon sugar, which has a hydroxyl group on the 2' carbon. DNA uses deoxyribose, which lacks that 2' hydroxyl (it has a hydrogen instead). Because ribose has the 2' OH, the molecule containing ribose is RNA. This difference also helps explain why RNA is typically less stable than DNA: the 2' hydroxyl makes RNA more prone to hydrolysis, while DNA’s extra stability comes from having deoxyribose. The sugar sits in the backbone of the nucleic acid, connected to phosphate groups and bases, so this difference directly influences their properties and roles in biology.

The sugar component distinguishes the two nucleic acids. RNA uses ribose as its five-carbon sugar, which has a hydroxyl group on the 2' carbon. DNA uses deoxyribose, which lacks that 2' hydroxyl (it has a hydrogen instead). Because ribose has the 2' OH, the molecule containing ribose is RNA. This difference also helps explain why RNA is typically less stable than DNA: the 2' hydroxyl makes RNA more prone to hydrolysis, while DNA’s extra stability comes from having deoxyribose. The sugar sits in the backbone of the nucleic acid, connected to phosphate groups and bases, so this difference directly influences their properties and roles in biology.