Which nutrient is essential for the formation of nucleotides?

Phosphates are essential for the formation of nucleotides because each nucleotide, which serves as the building block of nucleic acids like DNA and RNA, consists of three components: a phosphate group, a sugar molecule, and a nitrogenous base. The phosphate group is critical because it provides the structural framework for the formation of the nucleic acid polymer. During the synthesis of DNA and RNA, nucleotides link together via phosphodiester bonds, which involve the phosphate group of one nucleotide bonding to the sugar of another. Without phosphates, nucleotides cannot be formed, and thus the synthesis of DNA and RNA would not be possible.

While calcium plays important roles in various physiological processes, it is not a component of nucleotides. Nitrogen is involved in forming the nitrogenous bases of nucleotides, but it is the phosphate groups that are directly responsible for the actual structure and connectivity of the nucleotides themselves. Glucose, while a crucial energy source for cells and involved in carbohydrate metabolism, does not play a direct role in nucleotide synthesis. Therefore, phosphates are the correct answer as they are a fundamental component required for nucleotide formation.