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2 definitions found
 for deoxyribonucleic acid
From The Collaborative International Dictionary of English v.0.48 :

  deoxyribonucleic acid \deoxyribonucleic acid\ n.
     a nucleic acid, usually of very high molecular weight,
     consisting of a linear sequence of monomer units of
     deoxyribonucleotides, occurring in most organisms in pairs of
     strands, wound together in the form of a double helix; it is
     the main component of chromosomes and contains the genetic
     information which is the basis of heredity, transmitted from
     parent to progeny, and found in all living organisms except
     for certain viruses which have RNA as their basic genetic
     material; -- usually referred to by the acronym DNA.
  
     Syn: DNA, desoxyribonucleic acid.
          [PJC]
  
     Note: The monomer units making up the DNA each contain one of
           four heterocyclic bases: thymine, adenine, cytosine, or
           guanine. The genetic information is contained in the
           precise sequence of these monomer units, which
           ultimately specify the sequence of proteins to be made
           by the organism's biosynthetic processes, mediated
           through the synthesis of RNA having a base sequence
           corresponding to that of the DNA. The DNA sequence also
           specifies the sequence of the various RNA molecules the
           RNA base sequence being a copy of that on one of the
           DNA strands. Most of the RNA synthesized is involved in
           protein synthesis. In the double-helical form of DNA,
           the thymine on one strand is paired with the adenine on
           the opposite strand, and cytosine of one strand is
           paired with guanine on the opposite strand. There is in
           DNA also certain controlling information concerning the
           timing and amount of RNA to be made, encoded within the
           sequence of the DNA in ways that are still being
           elucidated.
           When this structure is replicated in the course of cell
           multiplication, two identical double-helical molecules
           are formed, each containing one strand from the
           original molecule. Each resulting molecule is
           distributred to either the parent or progeny organism,
           and this is the basic mechanism for transmission of
           hereditary information. In RNA-based viruses, or those
           having single strands of DNA (as certain viruses), the
           genetic information transmission occurs through a
           double-stranded intermediate by a similar mechanism.
           In some organisms slight modifications of the bases of
           DNA are found, such as methylcytosine or, in some
           viruses, uracil or hydroxymethyluracil; these unusual
           bases act analogously to the normal bases in their
           genetic coding function. A small percentage of
           methylcytosine is found in many organisms, and it
           serves in some cases as a special signal, as for
           restriction enzymes.
           [PJC]

From WordNet (r) 3.0 (2006) :

  deoxyribonucleic acid
      n 1: (biochemistry) a long linear polymer found in the nucleus
           of a cell and formed from nucleotides and shaped like a
           double helix; associated with the transmission of genetic
           information; "DNA is the king of molecules" [syn:
           deoxyribonucleic acid, desoxyribonucleic acid, DNA]

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