Which nitrogenous base is unique to RNA?

Uracil is the nitrogenous base that is unique to RNA. While DNA contains thymine as one of its four bases, RNA substitutes uracil for thymine. This distinction is important in molecular biology as it influences the structure and function of RNA.

In addition to uracil, both RNA and DNA share other bases. For example, guanine and adenine are found in both nucleic acids, which means they do not differentiate between DNA and RNA. Thymine, on the other hand, is exclusive to DNA. Thus, recognizing uracil as a key component of RNA highlights its role in gene expression and protein synthesis, underlining the varying functions that RNA serves compared to DNA.