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    During the process of transcription, how is the mRNA strand (that forms) single stranded. Because doesn't the free RNA nucleotides get hydrogen bonded to the DNA nucleotides (exposed) and therefore the mRNA is double stranded as it has bonded to the DNA exposed nucleotides on the template strand......
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    (Original post by mil88)
    During the process of transcription, how is the mRNA strand (that forms) single stranded. Because doesn't the free RNA nucleotides get hydrogen bonded to the DNA nucleotides (exposed) and therefore the mRNA is double stranded as it has bonded to the DNA exposed nucleotides on the template strand......
    After the free RNA nucleotides match up to the bases on the DNA, and phosphodiester bonds form, making the nucleotides all one strand, the RNA molecule separates from the DNA molecule and the unwinded DNA reforms, leaving the RNA single stranded.

    If it were double stranded, it would be too big to leave through the nuclear pores - and it cannot carry a strand of DNA since its too precious; it is the original and only copy of DNA, and it can easily get damaged or broken outside the nucleus so no part of the DNA can be part of RNA.
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    (Original post by Nisr123)
    After the free RNA nucleotides match up to the bases on the DNA, and phosphodiester bonds form, making the nucleotides all one strand, the RNA molecule separates from the DNA molecule and the unwinded DNA reforms, leaving the RNA single stranded.

    If it were double stranded, it would be too big to leave through the nuclear pores - and it cannot carry a strand of DNA since its too precious; it is the original and only copy of DNA, and it can easily get damaged or broken outside the nucleus so no part of the DNA can be part of RNA.
    Oh I see, so do hydrogen bonds form between the RNA nucleotides and exposed DNA nucleotides and then break to form the single mRNA strand, or do they never form in the first place?
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    (Original post by mil88)
    Oh I see, so do hydrogen bonds form between the RNA nucleotides and exposed DNA nucleotides and then break to form the single mRNA strand, or do they never form in the first place?
    From my understanding, they form and break.
 
 
 
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