Question

If the total amount of adenine and thymine in a double-stranded DNA is 45%, the amount of guanine in this DNA will be

• A. 22.5%
• B. 27.5%
• C. 45%
• D. 55%

Answer 1

The correct option is B 27.5%

In a DNA segment, the amount of adenine is equal to that of thymine. According to given information, adenine and thymine constitute 45% of DNA. So, guanine and cytosine will constitute 55%.

Amount of guanine is equal to cytosine. So, amount of guanine in DNA will be 55/2 = 27.5%.