Answer:
If a DNA molecule has 30% Adenine the percentage of the other bases is Thymine: 30% Cytosine: 20% Guanine: 20%.
Explanation:
When the percentage that a base has in a DNA molecule is given, the percentage of the other bases can be known using the Chargaff's base pair rule.
A DNA molecule has the information of the genome of a living being, according to a specific sequence of its nitrogenous bases adenine, guanine, cytosine and thymine.
Chargaff was able to establish that in a DNA molecule the ratio of purine : pyrimidine of 1:1, so there must be the same amount of thymine as adenine and a similar amount of guanine for the cytosine, taking into account the complementarity of bases.
Taking into account the law of the base pair, if in a DNA chain there is 30% of Adenine, in the molecule there is:
- <em>Adenine 30%.
</em>
- <em>Thymine 30%.
</em>
- <em>Cytosine 20%.
</em>
- <em>Guanine 20%.
</em>
- <em>Total ..... 100%
</em>
In this case, the <u>Chargaff rule is useful to determine the percentage of nitrogenous bases that exist in a DNA molecule, knowing the percentage of a single base</u>.
