Comparison Between DNA and RNA -
DNA |
RNA |
1. DNA is the usual genetic material |
1. RNA is the genetic material of some viruses. |
2. DNA is usually double-stranded, (In certain viruses DNA is single stranded, e.g. φ X 174). |
2. Most cellular RNA is single stranded. (Some viruses e.g. reovirus, have double stranded RNA). |
3. The pentose sugar is deoxyribose. |
3. The pentose sugar is ribose. |
| 4. The common organic bases are adenine, guanine, cytosine and thymine. | 4. The common organic bases are adenine, guanine, cytosine and uracil. |
| 5. Base pairing: adenine pairs with thymine and guanine with cytosine. | 5. Adenine pairs with uracil and guanine with cytosine. |
| 6. Pairing of bases is throughout the length of the molecule. | 6. Pairing of bases is only in the helical region |
7. There are fewer uncommon bases |
7. There are more uncommon bases. |
| 8. DNA is only of one type | 8. There are three types of RNA messenger ribosomal and transfer RNA. |
| 9. Most of the DNA is found in the chromosomes. Some DNA is also found in the cytoplasm e.g. in mitochondria and chloroplasts. | 9. Messenger RNA is formed on the chromosomes, and is found in the nucleolus and cytoplasm. rRNA and tRNA are also formed on the chromosomes, and are found in cytoplasm. |
| 10. Denaturation (melting) is partially reversible only under certain conditions of slow cooling (renaturation). | 10. Complete and practically in stantaneous reversibility of the process of melting. |
11. Sharp, narrow temperature interval of transition in melting. |
11. Broad temperature interval of transition in melting. |
| 12. DNA on replication forms DNA, and on transcription forms RNA. | 12. Usually RNA does not replicate or transcribe. (In certain viruses RNA can synthesize an RNA chain). |
| 13. Genetic messages are usually encoded in DNA. | 13. The usual function of RNA is translating messages encoded in DNA into proteins. |
| 14. DNA consists of a large number of nucleotides, up to 4.3 million | 14. RNA consists of fewer nucleotides, up to 12,000. |