MCQ
The pyrimidine bases present in $DNA$ are
- ✓cytosine and thymine
- Bcytosine and uracil
- Ccytosine and adenine
- Dcytosine and guanine
✓
Answer
Correct option: A.
cytosine and thymine
a
Thus, in $DNA$, the purines adenine $(A)$ and guanine $(G)$ pair up with the pyrimidines thymine $(T)$ and cytosine $(C)$, respectively. In $RNA$, the complement of adenine $(A)$ is uracil $(U)$ instead of thymine $(T)$, so the pairs that form are adenine:uracil and guanine:cytosine.
Thus, in $DNA$, the purines adenine $(A)$ and guanine $(G)$ pair up with the pyrimidines thymine $(T)$ and cytosine $(C)$, respectively. In $RNA$, the complement of adenine $(A)$ is uracil $(U)$ instead of thymine $(T)$, so the pairs that form are adenine:uracil and guanine:cytosine.
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