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: dna

  1. #1
      Eiman
    Jul 2011
    -
    14,750

    dna


    DNA
    DNA 1953 J. Watson and F. Crick . DNA Self-duplication .


    The Structure of DNA


    DNA . Nucleotides Long polymer . DNA Nucleotide Deoxyribose phosphate Nitrogen base

    Purines ( A ) Adenine Guanine ( G ) Pyrimidines Thymine ( T ) Cytosine ( C ). Sugar-Phosphate backbone .


    3,5 phosphodiester linkage . DNA . . ( ) .

    The5`end The3`end .

    phosphodiester linkage Deoxyribose Backbone DNA .

    DNA


    DNA X-ray diffraction ( ) Rosalind Franklin M.H.F. Wilkins . ( ). . ( Phosphorus Oxygen) .

    .

    ( ) . Mathematical analysis .

    DNA . X-ray DNA . DNA 0.34 3.4 2 . Nucleotide bases ( ) . DNA . DNA Two nucleotide chains . . .



    DNA

    1950 DNA : DNA ( )

    ( A ) ( T ) ( G ) ( c ) . A T C G (G=C) A=T) and )


    X=ray diffraction (DNA) ( C ) ( T ) ( G ) ( A ) . DNA 2 Nanometers . ( 1.2 ) .

    . ( A ) ( T ) ( C ) ( G ) ( T ) ( A ) ( ) Two Hydrogen Bonds (C) ( G ) . ( A ) ( T ) ( C )

    ( G ) . Complementary . .


    3\_____AGTC ACTG_____5\



    5\_____TCAGTGAC_____3\

    DNA DNA . DNA .



    DNA ( A ) Adenine Thymine ( C ) Cytosine ( C ) Guanine ( G ) .






    .......

  2. #2

    Jan 2013
    6,984

    : dna



  3. #3

    Dec 2012
    158

    : dna


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