Cytidine nucleotides are essential building blocks of RNA, composed of a nitrogenous base called cytosine, a sugar molecule known as ribose, and one or more phosphate groups. They play a crucial role in various biological processes, including protein synthesis and cellular signaling. In addition to their structural role in RNA, cytidine nucleotides are involved in energy transfer within cells, particularly through cytidine triphosphate (CTP). CTP is vital for synthesizing lipids and other biomolecules, highlighting the importance of cytidine nucleotides in cellular metabolism and function.