What role do nucleotides play in the structure of DNA and RNA?

Nucleotides are indeed the fundamental building blocks of both DNA and RNA. Each nucleotide consists of three components: a nitrogenous base, a five-carbon sugar, and a phosphate group. In DNA, the sugar is deoxyribose, while in RNA, it is ribose.

When nucleotides link together through phosphodiester bonds, they form long chains, which are essential for creating the polymer structures of DNA and RNA. The specific sequence of these nucleotides encodes the genetic information crucial for the functions and development of living organisms. This sequence is what enables the synthesis of proteins and the transmission of genetic information during processes such as replication and transcription.

In contrast, the other options present roles that do not align with the primary function of nucleotides in this context. While nucleotides can also play roles in energy transfer (for example, ATP as an energy carrier), their primary significance in the structure of nucleic acids lies in being the building blocks that form the backbone of these essential biological molecules.