The element essential for the synthesis of DNA is phosphorus. Phosphorus is a key component of nucleotides—the building blocks of DNA and RNA—forming a crucial part of the backbone structure of these molecules. This element plays a vital role in cellular functions, including energy transfer through molecules like ATP and the regulation of various biochemical pathways. Phosphorus is also essential for plant growth and health, impacting agricultural practices. Understanding phosphorus's function in DNA synthesis is crucial within genetics, biology, and biochemistry fields.