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.
Read the rest of this article: http://en.wikipedia.org/wiki/DNA
_______________________________ Today's selected anniversaries:
1689: Glorious Revolution: Instead of James Francis Edward Stuart the Prince of Wales acceding to the throne, his sister Mary and her husband William were proclaimed co-rulers of England. (http://en.wikipedia.org/wiki/Mary_II_of_England) (http://en.wikipedia.org/wiki/William_III_of_England)
1880: Thomas Edison observed the Edison Effect, which later formed the basis of John Ambrose Fleming's vacuum tube diodes. (http://en.wikipedia.org/wiki/Thermionic_emission)
1945: The RAF Bomber Command began the strategic bombing of Dresden in Saxony, Germany, resulting in a lethal firestorm which killed tens of thousands of civilians. (http://en.wikipedia.org/wiki/Bombing_of_Dresden_in_World_War_II)
1984: Konstantin Chernenko succeeded the late Yuri Andropov as General Secretary of the Communist Party of the Soviet Union. (http://en.wikipedia.org/wiki/Konstantin_Chernenko)
2004: Researchers at Harvard University discovered BPM 37093, the universe's largest known diamond, white dwarf star. (http://en.wikipedia.org/wiki/BPM_37093)
_____________________ Wikiquote of the day:
Every man's life (and ... every woman's life), awaits the hour of blossoming that makes it immortal ... love is a divinity above all accidents, and guards his own with extraordinary obstinacy. -- Eleanor Farjeon (http://en.wikiquote.org/wiki/Eleanor_Farjeon)