Difference between DNA and RNA
Comparison | DNA | RNA |
Full Name | Deoxyribonucleic Acid | Ribonucleic Acid |
Function | DNA replicates and stores genetic information. It is a blueprint for all genetic information contained within an organism | RNA converts the genetic information contained within DNA to a format used to build proteins, and then moves it to ribosomal protein factories. |
Structure | DNA consists of two strands, arranged in a double helix. These strands are made up of subunits called nucleotides. Each nucleotide contains a phosphate, a 5-carbon sugar molecule and a nitrogenous base. | RNA only has one strand, but like DNA, is made up of nucleotides. RNA strands are shorter than DNA strands. RNA sometimes forms a secondary double helix structure, but only intermittently. |
Length | DNA is a much longer polymer than RNA. A chromosome, for example, is a single, long DNA molecule, which would be several centimetres in length when unravelled. | RNA molecules are variable in length, but much shorter than long DNA polymers. A large RNA molecule might only be a few thousand base pairs long. |
Sugar | The sugar in DNA is deoxyribose, which contains one less hydroxyl group than RNA’s ribose. | RNA contains ribose sugar molecules, without the hydroxyl modifications of deoxyribose. |
Bases | The bases in DNA are Adenine (‘A’), Thymine (‘T’), Guanine (‘G’) and Cytosine (‘C’). | RNA shares Adenine (‘A’), Guanine (‘G’) and Cytosine (‘C’) with DNA, but contains Uracil (‘U’) rather than Thymine. |
Base Pairs | Adenine and Thymine pair (A-T) Cytosine and Guanine pair (C-G) | Adenine and Uracil pair (A-U) Cytosine and Guanine pair (C-G) |
Location | DNA is found in the nucleus, with a small amount of DNA also present in mitochondria. | RNA forms in the nucleolus, and then moves to specialised regions of the cytoplasm depending on the type of RNA formed. |
Reactivity | Due to its deoxyribose sugar, which contains one less oxygen-containing hydroxyl group, DNA is a more stable molecule than RNA, which is useful for a molecule which has the task of keeping genetic information safe. | RNA, containing a ribose sugar, is more reactive than DNA and is not stable in alkaline conditions. RNA’s larger helical grooves mean it is more easily subject to attack by enzymes. |
Ultraviolet (UV) Sensitivity | DNA is vulnerable to damage by ultraviolet light. | RNA is more resistant to damage from UV light than DNA. |