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  #1  
Old 10-22-2012
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DNA What would be the DNA codon?

Q)A molecular biologist encountered a t RNA molecule which carried GAA at it's mRNA binding site he was wondering what would be the template on the DNA that coded for the amino acid...?...(note---assume the codons as in 5' -3' if not given)..

a) AAG
B) UUC
C) CUU
D) TTA
E) ATT
F) GAA
G) AUU
H) UAA
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  #2  
Old 10-23-2012
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UUC is it?
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Old 10-23-2012
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F: GAA
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Old 10-23-2012
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my ans is UUC
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Old 10-23-2012
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GAA?......
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Old 10-23-2012
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Quote:
Originally Posted by nishaa View Post
UUC is it?
hey i think you missed a small "t" in front of RNA.........
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Old 10-23-2012
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I think it should be TTA.
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Old 10-23-2012
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Quote:
Originally Posted by venky2600 View Post
Q)A molecular biologist encountered a t RNA molecule which carried GAA at it's mRNA binding site he was wondering what would be the template on the DNA that coded for the amino acid...?...(note---assume the codons as in 5' -3' if not given)..

a) AAG
B) UUC
C) CUU
D) TTA
E) ATT
F) GAA
G) AUU
H) UAA
I would choose B) UUC. Is it a tricky question?
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Old 10-23-2012
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Quote:
Originally Posted by venky2600 View Post
q)a molecular biologist encountered a t rna molecule which carried gaa at it's mrna binding site he was wondering what would be the template on the dna that coded for the amino acid...?...(note---assume the codons as in 5' -3' if not given)..

A) aag
b) uuc
c) cuu
d) tta
e) att
f) gaa
g) auu
h) uaa
........................................
F gaa
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Old 10-23-2012
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I will change my answer to F) GAA, because the answer that I gave earlier UUC is the sequence for the mRNA and the question asks about the DNA sequence. I should have paid more attention
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Old 10-23-2012
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The tRNA has GAA

mRNA should have CUU (5' to 3')

Coding strand is supposed to be identical in sequence to the mRNA transcript except for the presence of thymine instead of uracil.

Coding strand: CTT

Template: AAG

Took my time to do it this time. Still feel something's not quite right
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Old 10-23-2012
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[QUOTE=volvo;156946]The tRNA has GAA

mRNA should have CUU (5' to 3')


GAA is 5'-3' and mRNA CUU is 3'-5' and if you read it 5'-3' is UUC.
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  #13  
Old 10-23-2012
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Thanks for correcting me
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Old 10-23-2012
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Correct Answer F is right

never saw these many varied answers to my question before

the correct answer is F) GAA........

Those who correctly answered--well done ; remaining ----well tried..

i guess the stem is little complicated (to me atleast)...and also i think explanation too is little complicated..but i'll try my best to explain...

here tRNA molecule have..GAA at mRNA binding site.....
assume it is in 5'-3' direction------so tRNA and mRNA reading occurs in complimentary and antiparallel with tRNA in 3'-5'.......so changing tRNA to 3' AAG 5'.......... so the complimentary mRNA formed would be 5' UUC 3' (i see many of them stuck here)

the question asked the template DNA strand codon.......so, mRNA formed in 5'-3' direction from template strand (which is 3'-5').......
so by complimentating them we get to the answer--------------> 5'UUC3' mRNA will be formed from 3' AAG 5' template strand........

again this is not the answer coz the options if not gives assume they are in 5' -3' ...so 5'GAA3' is the answer....


summary------

tRNA ----3' AAG 5'
mRNA----5' UUC 3'
template strand DNA----- 3' AAG5'
coding strand DNA-------5' TTC 3'



hope it understands.....thanks
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  #15  
Old 10-25-2012
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Aww, i guess i am good at molecular, coz i answered it immediately without much thinking, thanx for the question
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  #16  
Old 10-25-2012
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Thumbs Up UUC is the answer

..

a) AAG
B) UUC
C) CUU
D) TTA
E) ATT
F) GAA
G) AUU
H) UAA
[/QUOTE]
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Old 10-26-2012
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Quote:
Originally Posted by venky2600 View Post
Q)A molecular biologist encountered a t RNA molecule which carried GAA at it's mRNA binding site he was wondering what would be the template on the DNA that coded for the amino acid...?...(note---assume the codons as in 5' -3' if not given)..

a) AAG
B) UUC
C) CUU
D) TTA
E) ATT
F) GAA
G) AUU
H) UAA
F. GAA (its asking about DNA template )
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