In sea urchin DNA, which is double stranded, 17% of the

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In sea urchin DNA, which is double stranded, 17% of the bases were shown to be cytosine. The percentages of the other three bases expected to be present in this DNA are:

1. G 17%, A 16.5%, T 32.5%
2. G 17%, A 33%, T 33%
3. G 8.5%, A 50%, T 24.5%
4. G 34%, A 24.5%, T 24.5%

Correct Option: B

Chargaff’s rule states that A = T and G ≡ C. The molar amount of adenine = molar amount of thymine. The molar amount of guanine = molar amount of cytosine.
Hence, G is 17%, so,
C = 17% A = 33%,
so, T = 33%