In a DNA percentage of thymine is 20% then what is the percentage of guanine : -
- 40%
- 20%
- 30%
- 60%
Answer
(3) 30%
Solution
As per Chargaff's rule (NCERT), in double-stranded DNA A = T and G = C.
∵ T = 20% ⇒ A = 20%
⇒ A + T = 40%
⇒ G + C = 100% − 40% = 60%
∴ G = 60\%2 = 30%
Answer: (3)