Answer:
For sample A, A=17.7 %, T=17.7 %, G=32.30%, C=32.30%
For sample B, A= 28.9%, T=28.9%, G= 21.10%, C= 21.10%
Explanation:
The composition of nitrogenous bases in DNA is calculated using the suggestions proposed by the results of the experiment performed by Erwin Chargaff.
He found that in a DNA sample the composition of purine to pyrimidine is 1:1. This indicates that the amount of purine equals pyrimidine. This can be presented as purines + pyrimidines= 100. Also, adenine binds thymine and cytosine binds guanine.
In the given question,
<u>For sample A
</u>
A= 17.7 %, Therefore, thymine will be = 17.7 %,
A+T= 35.40%
Now, G+C=100- 35.40%
G+C= 64.60%
content of G= 64.60/2= 32.30%
content of C= 32.30%
<u>For sample B
</u>
T=28.9%, A will be= 28.9%
A+T= 57.80%
G+C=100-57.80%
G+C= 42.20%
Thus content of G will be= 42.20/2=21.10
content of C= 21.10%
Thus,
For sample A, A=17.7 %, T=17.7 %, G=32.30%, C=32.30%
For sample B, A= 28.9%, T=28.9%, G= 21.10%, C= 21.10%
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