In a DNA, the percentage of thymine is 20%. What will be the percentage of guanine?
Correct answer: C. 30%
- A. 20%
- B. 40%
- C. 30%
- D. 60%
Explanation
In a DNA, the percentage of guanine is equal to the percentage of cytosine, and the percentage of adenine is equal to the percentage of thymine. This is because the two strands of DNA are complementary, meaning that A always pairs with T, and G always pairs with C. If the percentage of thymine is 20%, then the percentage of adenine must also be 20%. This means that the percentage of guanine + cytosine must be 60%. Since the percentage of cytosine is equal to the percentage of guanine, the percentage of guanine must be 30%.
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