What is RNA primarily used for in cellular biology?

RNA primarily serves as a crucial intermediary in the process of gene expression. Specifically, messenger RNA (mRNA) is synthesized during transcription, where it forms a template based on the DNA code through complementary base pairing. This process involves RNA polymerase, which reads the DNA sequence and synthesizes a corresponding RNA strand. The mRNA then carries this genetic information from the nucleus to the ribosomes in the cytoplasm, where it is translated into proteins.

This function highlights RNA's role not just as a carrier of information but as an essential player in the flow of genetic instructions from DNA to protein synthesis. While other options refer to other roles that nucleic acids and cellular components play, they do not pertain to the primary function of RNA in cellular biology. For example, DNA is primarily responsible for storing genetic information, and energy production is mainly performed by organelles such as mitochondria rather than RNA.