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How is RNA different from DNA?
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Biology
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DNA and RNA are essential nucleic acids that differ in their chemical composition, structure, and biological roles.12
Key Differences
- Sugar Composition: DNA contains the sugar deoxyribose, while RNA contains ribose. The ribose in RNA has a 2β²-hydroxyl group that makes the molecule more chemically reactive and less stable than DNA.134
- Nitrogenous Bases: Both molecules use adenine, guanine, and cytosine. However, DNA uses thymine, whereas RNA uses uracil.142
- Molecular Structure: DNA typically exists as a stable double helix, consisting of two complementary strands. In contrast, RNA is usually single-stranded, allowing it to fold into complex three-dimensional shapes through internal base pairing.132
- Function: DNA serves as the master blueprint for life, storing genetic information. RNA acts as an intermediary that uses DNA's code to synthesize proteins, though it also functions as the genetic material for some viruses.132
Because RNA is constantly synthesized and degraded, its inherent chemical instability is generally not a disadvantage for the cell.3