How does DNA differ from RNA?

The distinction between DNA and RNA regarding the nitrogenous bases is a key difference. DNA contains the base thymine, while RNA has uracil in place of thymine. This base-pairing difference is significant because it plays a crucial role in the processes of transcription and translation within cells.

In DNA, the base pairings include adenine pairing with thymine and cytosine pairing with guanine, which is a fundamental aspect for the stability and structure of the double helix. Conversely, RNA substitutes uracil for thymine, which allows for the formation of RNA molecules that can perform various functions, such as acting as a messenger (mRNA) or a structural component (rRNA) in the ribosome.

This difference in nitrogenous bases is not merely about composition; it reflects the differing roles and functionalities of DNA and RNA within biological systems. DNA serves primarily as the storage medium for genetic information, while RNA plays critical roles in the expression and translation of that information into proteins.