Chemistry Double-stranded DNA molecule is 22% cytosine

[wwwaazup]

i am stuck on this problem and was hoping someone could help..

If a double-stranded DNA molecule is 22% cytosine, what are the percentages of guanine, adenine, and thymine?

Thanks

 

[Borek]

Hint: there will be the same amount of one of the other three.

 

[wwwaazup]

thanks, so 26% each

 

[Borek]

Which each, and why 26%?

 

[wwwaazup]

if 22% is is cytosine, i subtract 22 from 100 and get 78, then i divided that by 3 which is 26
so there is 26%, guanine, 26% adenine, and 26% thymine..

Right??

 

[Borek]

No, there must be other base that is present in exactly 22% quantity. Do you know how they pair?

 

[wwwaazup]

T & A pair and C & G pair..
so what are the steps i need to take?

 

[Borek]

so what are the steps i need to take?

Thinking will be enough. If there is 22% of C, how much G do you expect?

 

[wwwaazup]

So the hint u gave me was that there will be the same amount of one of the other three.
Then u said there must be other base that is present in exactly 22% quantity...

im soo lost please help!

 

[GCT]

If C pairs with G then there must be equal amounts of each assuming this is good DNA. Draw pictures if it helps.

 

[Borek]

So the hint u gave me was that there will be the same amount of one of the other three.
Then u said there must be other base that is present in exactly 22% quantity...

Perhaps my English fails me, but from what I understand you have stated twice exactly the same.