DNA and RNA are chiral molecules due to their structural components. Both contain pentose sugars: DNA contains deoxyribose and RNA contains ribose. These are D-sugars with multiple chiral centers (at C2, C3, and C4 in the furanose ring). The D-designation comes from the stereochemical configuration at the chiral center furthest from the carbonyl carbon. The chiral centers in these sugar moieties are the primary source of chirality in nucleic acids, making them optically active molecules. While the phosphate units and bases also contribute to molecular structure, the fundamental chirality arises from the D-sugar component.
Both human DNA and RNA are chiral molecules. The chirality in DNA and RNA arises due to the presence of
JEE Main 2026 — Chemistry Organic Chemistry
2026mcqeasy
Both human DNA and RNA are chiral molecules. The chirality in DNA and RNA arises due to the presence of
Official previous-year question
Held on 23 Jan 2026 · Verified 6 Jul 2026.
Options
- A
L-sugar component
- B
Chiral phosphate unit
- C
Base unit
- D
D-sugar component
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