Question

Which one is the structure of Uracil in RNA?

• A. It is a purine base with a double ring
• B. It is similar to thymine (5-methyl uracil), but lacks the methyl group
• C. It only binds with deoxyribose sugar
• D. It forms hydrogen bonds with guanine

Hint:

\[ \boxed{\text{Uracil (RNA) ↔ Adenine pairing}} \] \[ \boxed{\text{Thymine (DNA) = Uracil + CH}_3} \]

Answer 1

The Correct Option is B

Uracil is a pyrimidine base found exclusively in RNA, replacing thymine of DNA. It possesses two carbonyl groups at positions C2 and C4 of its six-membered ring but lacks the methyl group at C5 that distinguishes thymine. Uracil pairs with adenine via two hydrogen bonds during transcription and translation.