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Old 03-22-2013
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DNA RNA Polymerase or Reverse Transcriptase

I'm a bit curious as to why the answer isn't RNA polymerase, since it's responsible for causing transcription from DNA --> RNA. However, the answer is C for this question.


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Old 03-22-2013
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Look at the process as a whole... you are synthesizing DNA via an RNA intermediate. partial dsDNA > ds DNA > ssRNA > RNA/DNA hybrid ---> dsDNA (using RNA temp).

Only one enzyme can help synthesize progeny dsDNA from original partially dsDNA in the Hep B Virus and that's reverse transcriptase.

What NBME was this from by the way?
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Old 03-22-2013
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Hmm.. I was of the understanding that Hep B viral DNA polymerase (aka reverse transcriptase) uses an mRNA copy of the viral genome (made in the cell by host RNA polymerase) to first make an RNA/DNA hybrid, then use the DNA part of the hybrid to make the final double stranded DNA (which is circular).

Are you sure you have right answer key?
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Old 03-22-2013
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From the video it seems step 2 is by RNA polymerase, while step 3 and consecutive steps are by reverse transcriptase.
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Old 03-22-2013
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Ooops, I overlooked that! :/ Scratch my last post. *wondering what I was thinking* lol!
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Genetics-, Molecular-Biology-, Step-1-Questions, Videos-Animations

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