Which statement is accurate about the sugars in DNA and RNA?

Which statement is accurate about the sugars in DNA and RNA?

• A. DNA uses ribose sugar.
• B. RNA uses deoxyribose sugar.
• C. Only the 3' end of the sugar is involved in linking nucleotides.
• D. RNA uses ribose sugar and DNA uses deoxyribose sugar.

Answer: (D)

The sugars in DNA and RNA differ in a way that changes their chemistry and function: DNA uses deoxyribose, which lacks a 2' hydroxyl group, while RNA uses ribose, which has a 2' hydroxyl. This small difference makes DNA more chemically stable, suitable for long-term genetic storage, and allows RNA to be more reactive and flexible, supporting diverse structures and catalytic roles. Nucleotides are linked by phosphodiester bonds between the 3' hydroxyl of one sugar and the 5' phosphate of the next, so both ends are involved in chain formation; saying only the 3' end is involved isn’t accurate. Hence, the correct statement is that RNA uses ribose sugar and DNA uses deoxyribose sugar.

The sugars in DNA and RNA differ in a way that changes their chemistry and function: DNA uses deoxyribose, which lacks a 2' hydroxyl group, while RNA uses ribose, which has a 2' hydroxyl. This small difference makes DNA more chemically stable, suitable for long-term genetic storage, and allows RNA to be more reactive and flexible, supporting diverse structures and catalytic roles. Nucleotides are linked by phosphodiester bonds between the 3' hydroxyl of one sugar and the 5' phosphate of the next, so both ends are involved in chain formation; saying only the 3' end is involved isn’t accurate. Hence, the correct statement is that RNA uses ribose sugar and DNA uses deoxyribose sugar.