Which of the following nitrogenous bases is found in RNA but not in DNA? MCQ with Answer and Explanation

Which of the following nitrogenous bases is found in RNA but not in DNA?
A. Guanine
B. Cytosine
C. Adenine
D. Uracil
Answer: Option D
Solution (By JKExamLibrary)
RNA contains uracil instead of thymine found in DNA. In DNA, adenine pairs with thymine; in RNA, adenine pairs with uracil. Adenine, guanine, and cytosine are common to both. Uracil is a pyrimidine base, structurally similar to thymine but lacking a methyl group. This distinction is used in genetic material identification and understanding transcription.

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