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Old 06-19-2012
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Default A sample DNA has...

A sample DNA has 10% A and 50% G. Which of the following statements is true:

A) This DNA has 10% T
B) This DNA has 10% U
C) This DNA has 50% C
D) This DNA could be a single stranded viral DNA
E) This DNA could be a double stranded viral DNA


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Old 06-19-2012
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its D....SINGLE STRANDED DNA.....this question is from kaplan notes right?????
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Old 06-19-2012
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Default :)

Quote:
Originally Posted by anomali View Post
its D....SINGLE STRANDED DNA.....this question is from kaplan notes right?????
I will post correct answer and the source in a couple of hours. Please be patient - I want other people to have a chance to answer the question without a spoiler Thanks
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Old 06-19-2012
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i think answer is d
chargaff's rules-%A=%T(%U ),%G=%C,%PURINES=%PYRIMIDINES IN DOUBLE -STRANDED DNA OR dsRNA (%U)
so by these rule if A IS 10% T SHOULD BE 10% AND %G+%C=100%-(10%+10%), 40%C AND 40%G ,SO DNA IS SINGLE-STRANDED
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Old 06-20-2012
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yup, its d for sure
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I've become so numb
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Old 06-20-2012
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Default correct answer :)

Correct answer id D) This DNA could be a single stranded viral DNA


Just a quick reminder: From calculation we can see that Chargaff's rule (% of A=T/U, % of C=G) doesn't apply here. And this rule applies to double-stranded DNA only.
So presented DNA can be a single-stranded DNA/RNA, viral or any other..

The question was based on what they talk about in Kaplan videos

Last edited by Casandra; 06-20-2012 at 08:42 AM.
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Old 06-20-2012
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It can't be E solely because the rule applies to double stranded DNA?
I'm forgetting such simple concepts
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Originally Posted by dockhi View Post
It can't be E solely because the rule applies to double stranded DNA?
I'm forgetting such simple concepts

correction form my side - the rule applies to double-stranded DNA and RNA.

In the previous post I was referring to that specific case where we had DNA. I meant only ds-, not only DNA.
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