Double-stranded DNA molecule is 22% cytosine

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Discussion Overview

The discussion revolves around a problem involving the percentage composition of nucleobases in a double-stranded DNA molecule, specifically when it is stated that cytosine constitutes 22% of the total bases. Participants are exploring how to determine the percentages of guanine, adenine, and thymine based on this information.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Conceptual clarification

Main Points Raised

  • One participant is trying to solve the problem by calculating the remaining percentage of bases after accounting for cytosine.
  • Another participant hints that there will be an equal amount of one of the other bases, suggesting a pairing relationship.
  • A participant proposes that if cytosine is 22%, then the remaining bases should be divided equally among guanine, adenine, and thymine, resulting in 26% each.
  • Another participant challenges this reasoning, indicating that there must be another base present in the same quantity as cytosine, prompting further inquiry into base pairing rules.
  • Participants discuss the pairing rules, noting that adenine pairs with thymine and cytosine pairs with guanine, which is essential for determining the correct percentages.
  • One participant expresses confusion about the hints provided and seeks further clarification on the steps needed to solve the problem.
  • Another participant suggests visual aids, such as drawings, to help understand the base pairing concept.
  • There is a noted repetition in the hints provided, leading to further confusion for one participant regarding the instructions given.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correct percentages of the bases. There are competing views on how to approach the problem, with some participants proposing equal distribution and others emphasizing the importance of base pairing rules.

Contextual Notes

Participants express uncertainty about the steps to take in solving the problem, and there are unresolved aspects regarding the interpretation of the hints and the application of base pairing rules.

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


thanks, so 26% each
 


Which each, and why 26%?
 


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??
 


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


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


wwwaazup said:
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?
 


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!
 
  • #10


If C pairs with G then there must be equal amounts of each assuming this is good DNA. Draw pictures if it helps.
 
  • #11


wwwaazup said:
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.
 

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