# Finding out amount of adenine from known amount of pyrimidine

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#1

Pyrimidines make up 29.5% of a DNA sample. FInd the percentage of adenine

Is this question even possible and shouldnt there be an equal amount of pyrimidines and pyrines???
0
3 years ago
#2
(Original post by Himtiaz)

Pyrimidines make up 29.5% of a DNA sample. FInd the percentage of adenine

Is this question even possible and shouldnt there be an equal amount of pyrimidines and pyrines???

OK - what do you know about the structure of bases, and base pairing rules?
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#3
(Original post by Reality Check)

OK - what do you know about the structure of bases, and base pairing rules?
That's all the information I'm given.

I know that A and T pair and C and G pair and that T and C are pyrimidines
0
3 years ago
#4
(Original post by Himtiaz)

Pyrimidines make up 29.5% of a DNA sample. FInd the percentage of adenine

Is this question even possible and shouldnt there be an equal amount of pyrimidines and pyrines???

Ok, so you need to know that the percentage in the complementary bases are going to be the same, so A and T will have the same and G and C will have the same. Pyrimidines are the bases T and C which have an overall percentage of 29.5%. Coming to write this I think you may have missed out something in the question.
If T and C have 29.5% then individually they would each have 14.75% which cannot be correct.
A-14.75%
T-14.75%
C-14.75%
G-14.75
All these only add up to 59%, so I think you might have missed some info from the question.
P.S pyrimidines and purines do not need to have the same percentage
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#5
(Original post by Anonymous619)
Ok, so you need to know that the percentage in the complementary bases are going to be the same, so A and T will have the same and G and C will have the same. Pyrimidines are the bases T and C which have an overall percentage of 29.5%. Coming to write this I think you may have missed out something in the question.
If T and C have 29.5% then individually they would each have 14.75% which cannot be correct.
A-14.75%
T-14.75%
C-14.75%
G-14.75
All these only add up to 59%, so I think you might have missed some info from the question.
P.S pyrimidines and purines do not need to have the same percentage
I checked the question and that was all the information i was given. Ill just bring it up with the teacher next lesson
0
3 years ago
#6
(Original post by Himtiaz)
I checked the question and that was all the information i was given. Ill just bring it up with the teacher next lesson
Hi, sorry for the misunderstanding, upon doing the question again I relieased I made a mistake.
Ok so you know the pyrimidines are T and C so T+C=29.5%. So T and C will have 14.25% each
This leaves us with 70.5% (100-29.5) so A+G=70.5%. So A and G will have 35.25% each.

A - 35.25%
T - 14.25%
G - 35.25%
C - 14.25%
Sorry for the silly mistake I made
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#7
't
(Original post by Anonymous619)
Hi, sorry for the misunderstanding, upon doing the question again I relieased I made a mistake.
Ok so you know the pyrimidines are T and C so T+C=29.5%. So T and C will have 14.25% each
This leaves us with 70.5% (100-29.5) so A+G=70.5%. So A and G will have 35.25% each.

A - 35.25%
T - 14.25%
G - 35.25%
C - 14.25%
Sorry for the silly mistake I made
But dont C and G have complementary pairing so dont they need to be equal?
0
3 years ago
#8
(Original post by Himtiaz)
't

But dont C and G have complementary pairing so dont they need to be equal?
Would it be possible to send a picture of the question, I think that there is key information missing, but other than that, this should be the answer
0
11 months ago
#9
Math wrong, 29.5/2 is 14.75 not 14.25
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