The primary component of nucleic acids, such as DNA and RNA, is the nucleotide. Nucleotides consist of three key parts: a phosphate group, a five-carbon sugar (ribose in RNA and deoxyribose in DNA), and a nitrogenous base (adenine, thymine, cytosine, or guanine in DNA; uracil replaces thymine in RNA). The sequence of nucleotides encodes genetic information, making nucleic acids essential for biological functions, including protein synthesis and inheritance.