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Old 07-02-2011
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DNA A question on RNA synthesis plz help!

Question: The base sequence of codons 57-58 in the cytochrome beta-5 reductase geneis CAGCGC. The mRNA produced upon transcription of this gene would be?

Answer: CAGCGC.................I wonder why? I mean shouldn't it be GCGCUG

Plz help asap
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Old 07-04-2011
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Because the coding strand, rather than the template strand, is given by default. This is sort of tricky, and just one of those things that is not as standard as we would like
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Old 07-04-2011
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Mondoshawan is exactly right.
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Old 07-04-2011
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this has been discussed here

Base codons and template versus coding strands!

i think it may be helpful
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Old 07-04-2011
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Actually, Mondoshawan, what is given in this question is the template strand not the coding strand
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Old 07-04-2011
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book is right
its answer 4

coding strand of DNA is
5`CAGCGC 3`

template strand will be

5`GCGCTG 3`

then mRNA strand is

5`CAGCGC 3`

as far as i know tahts it..plz correct me here too if its wrong...
Molecular biology ....transcription
(plz see question number 2 and make me correct there too)...
thanks.
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Old 07-05-2011
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Quote:
Originally Posted by IKR123 View Post
book is right
its answer 4

coding strand of DNA is
5`CAGCGC 3`

template strand will be

5`GCGCTG 3`

then mRNA strand is

5`CAGCGC 3`

as far as i know tahts it..plz correct me here too if its wrong...
Molecular biology ....transcription
(plz see question number 2 and make me correct there too)...
thanks.
ure absolutely correct these qs re really weired the key to solve is to look fr the area on DNA mentioned in the q stem as here its given codons which means its coding strand
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Old 07-05-2011
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But, key is to know whether the given sequence is template strand or coding strand. The word "codons" is used for mRNA sequence, therefore, we do not have to figure out whether it is template or coding strand, we can simply use the given strand sequence as the answer.

Please comment on this, as it is very confusing........ Bebix and heights, pls join in as well if you see this

IKR123, can you pls ask the instructor at Kaplan? Thanks a lot
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Old 07-06-2011
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sure i will ask @ kaplan BUT WITH RIGHT PROF LIKE SAM TURCO ..
so plz wait till then..
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