Which sugar is present in DNA, distinguishing it from RNA?

Which sugar is present in DNA, distinguishing it from RNA?

• A. Ribose
• B. Glucose
• C. Fructose
• D. Deoxyribose

Answer: (D)

The difference between DNA and RNA lies in the sugar component of their nucleotides. DNA uses deoxyribose, while RNA uses ribose. The key distinction is at the 2' carbon: deoxyribose has a hydrogen there (no hydroxyl group), whereas ribose has a hydroxyl group at the 2' position. This small change makes DNA’s backbone much more chemically stable, ideal for long-term genetic information storage, while the 2'-OH in RNA contributes to its greater reactivity and versatility. Therefore, the sugar present in DNA, distinguishing it from RNA, is deoxyribose. (Ribose is the sugar in RNA, and glucose/fructose are other metabolic sugars not used in the nucleic acid backbone.)

The difference between DNA and RNA lies in the sugar component of their nucleotides. DNA uses deoxyribose, while RNA uses ribose. The key distinction is at the 2' carbon: deoxyribose has a hydrogen there (no hydroxyl group), whereas ribose has a hydroxyl group at the 2' position. This small change makes DNA’s backbone much more chemically stable, ideal for long-term genetic information storage, while the 2'-OH in RNA contributes to its greater reactivity and versatility. Therefore, the sugar present in DNA, distinguishing it from RNA, is deoxyribose. (Ribose is the sugar in RNA, and glucose/fructose are other metabolic sugars not used in the nucleic acid backbone.)