Which nitrogen bases are found in RNA?

In RNA, the nitrogen bases present are adenine (A), guanine (G), cytosine (C), and uracil (U). This set reflects a crucial distinction between RNA and DNA, where thymine (T) is present instead of uracil. Uracil plays a critical role in RNA's structure and function, allowing it to participate in essential processes such as protein synthesis and gene expression.

Understanding the role of these nitrogen bases is fundamental to molecular biology and genetics, as they form the building blocks of RNA molecules, which serve various functions, including serving as templates for protein synthesis (mRNA), bringing amino acids to ribosomes (tRNA), and forming components of ribosomes themselves (rRNA). Thus, the correct identification of uracil in the context of RNA highlights an important aspect of nucleic acid biology.