Wikipedia:Today's featured article/February 13, 2007



DNA is a nucleic acid that contains the genetic instructions for the development and function of living organisms. All living things contain DNA, although DNA viruses are usually considered non-living. The main role of DNA in the cell is the long term storage of information. It is often compared to a blueprint, since it contains the instructions to construct other components of the cell, such as proteins and RNA molecules. The DNA segments that carry genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the expression of genetic information. In eukaryotes such as animals and plants, DNA is stored inside the cell nucleus, while in prokaryotes such as bacteria, the DNA is in the cell's cytoplasm. The major function of DNA is to encode the sequence of amino acid residues in proteins, using the genetic code. To read the genetic code, cells make a copy of a stretch of DNA in the nucleic acid RNA. These RNA copies can then be used to direct protein biosynthesis, but they can also be used directly as parts of ribosomes or spliceosomes. (more...)

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