Q150 / 180 · JIPMER 2019 · Zoology

In DNA $20 \%$ bases are adenine. What percentage of bases are pyrimidines?

  • A
    $30 \%$
  • B
    $60 \%$
  • Correct answer
    C
    $50 \%$
  • D
    $20 \%$

Solution

According to chargaff's rule $\mathrm{A}+\mathrm{G}=\mathrm{C}+\mathrm{T}=50 \%$ $\therefore \quad$ If $\mathrm{A}=20 \%$ then $\mathrm{T}=20 \%$ $\begin{aligned} \mathrm{C}+\mathrm{T} & =50 \% \\ \mathrm{C}=50 \%-20 \% & =30 \% \end{aligned}$ Total percentage of pyrimidine bases $(\mathrm{T}+\mathrm{Q}) \text { are } 20+30=50 \%$

Hence, the correct answer is option: 'C'.

Relevant Questions