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Nucleic acid question...

Discussion in 'MCAT: Medical College Admissions Test' started by Esteban, Jul 30, 2006.

  1. Esteban

    Esteban Senior Member
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    I have a question- it may seem stupid to some. I am reading EK's biology, and something doesn't make sense to me. It reads,

    "a nucleotide attached to the number 3 carbon (3') of its neighbor, follows that neighbor in the list. In other words, nucleotides are written 5' --> 3'."

    What're they referring to when they say "5'"? Thanks.
     
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  3. geno2568

    geno2568 Senior Member
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    they mean the 5' carbon. When you draw a ribose molecule, each carbon has a number. The 5' end of a nucleic acid is the end that has a 5' carbon exposed
     
  4. Sol Rosenberg

    Sol Rosenberg Long Live the New Flesh!
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    Minor nit. The 5' end has a phosphate (attached to the 5' carbon) exposed.
     
  5. TMP-SMX

    TMP-SMX Senior Member
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    Yes... And if you are confused as to what 3' and 5' are on the deoxyribose just think about the phosphate 5' and the definition of deoxyribose meaning the hydroxyl 3' right next to the "deoxy" 2' hydrogen is what receives the next nucleotide.
     
  6. Esteban

    Esteban Senior Member
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    Thanks! I guess I was tired when I was reviewing this :rolleyes:.
     

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