which molecules are the building blocks of dna?

DNA is built from nucleotides, the basic building blocks of nucleic acids. In DNA, each nucleotide contains three components: a deoxyribose sugar, a phosphate group, and a nitrogenous base (adenine A, thymine T, cytosine C, or guanine G). These nucleotides link together through phosphodiester bonds between the sugar of one nucleotide and the phosphate of the next, forming a sugar–phosphate backbone with the bases extending inward. Two DNA strands align in an antiparallel fashion to create the characteristic double helix, with base pairing (A with T via two hydrogen bonds, and C with G via three hydrogen bonds) bridging the two strands. This arrangement encodes genetic information in the sequence of bases along the strands.