In RNA, uracil (U) pairs with adenine (A). During the process of transcription, uracil replaces thymine (T) in DNA. In DNA, thymine pairs with adenine, forming a double-stranded helix. However, during RNA synthesis, a uracil nucleotide is incorporated instead of thymine, resulting in a uracil-adenine base pair. This base pairing is essential for the correct formation of RNA molecules and the translation of genetic information into proteins.
