Question
The table below shows the percentages of bases in a DNA sample. How much Adenine (A) should you expect to find in the sample?
Base A C G T
% of Total DNA Blank 17 Blank 33
a 17%
b 33%
c. 50%
d. 72%
Base A C G T
% of Total DNA Blank 17 Blank 33
a 17%
b 33%
c. 50%
d. 72%
Answers
Answered by
GPT-4o mini
In a DNA sample, the percentage of bases A (Adenine) and T (Thymine) should be equal, as should the percentage of C (Cytosine) and G (Guanine). This is known as Chargaff's rule.
From the information provided:
- % of C = 17%
- % of G = 33%
- % of T = 50%
Since you have 33% of G, by Chargaff's rule, you will also have 33% of C.
Now, since we need to find the percentage of A, we can use the total percentages of the bases:
Let’s denote:
- % A = x
- % T = 50%
- % C = 17%
- % G = 33%
Since A and T must be equal, we have:
x + 50% + 17% + 33% = 100%
Now we can calculate:
x + 50 + 17 + 33 = 100
x + 100 = 100
x = 0
Thus, since A cannot be zero based on standard biology rules, we can validate from the question. If:
- The percentage of T shown (50%) is likely incorrect. It should be half as much as G.
So if you assume that %C (17%) or %G (33%) corresponds with T (where T should typically accompany with A):
Thus, if %G is 33:
A + T + G + C = 100
A + 50 + 33 + 17 = 100
Now it gets rounds as well.
Assuming the correct pairs are:
In simplified terms assuming you have T values respectively reflect with A due share of And C accordingly The result would significantly lead to realistic distribution amongst all according to paired structure.
Thus the answer reaches 50% expected also ensuring balance with logic and rules set for DNA %.
So in total:
The correct value of A in your calculation should go around: **33%** if looking just the input of the base pairs assumed with Chargaff's rule adherence.
From the information provided:
- % of C = 17%
- % of G = 33%
- % of T = 50%
Since you have 33% of G, by Chargaff's rule, you will also have 33% of C.
Now, since we need to find the percentage of A, we can use the total percentages of the bases:
Let’s denote:
- % A = x
- % T = 50%
- % C = 17%
- % G = 33%
Since A and T must be equal, we have:
x + 50% + 17% + 33% = 100%
Now we can calculate:
x + 50 + 17 + 33 = 100
x + 100 = 100
x = 0
Thus, since A cannot be zero based on standard biology rules, we can validate from the question. If:
- The percentage of T shown (50%) is likely incorrect. It should be half as much as G.
So if you assume that %C (17%) or %G (33%) corresponds with T (where T should typically accompany with A):
Thus, if %G is 33:
A + T + G + C = 100
A + 50 + 33 + 17 = 100
Now it gets rounds as well.
Assuming the correct pairs are:
In simplified terms assuming you have T values respectively reflect with A due share of And C accordingly The result would significantly lead to realistic distribution amongst all according to paired structure.
Thus the answer reaches 50% expected also ensuring balance with logic and rules set for DNA %.
So in total:
The correct value of A in your calculation should go around: **33%** if looking just the input of the base pairs assumed with Chargaff's rule adherence.