DNA is always synthesized in the 5'-to-3' direction, meaning that nucleotides are added only to the 3' end of the growing strand. As shown in Figure 2, the 5'-phosphate group of the new nucleotide ...

whereas the other's runs in the 3' to 5' direction (Figure 4). It's also critical to understand that the specific sequence of A, T, C, and G nucleotides within an organism's DNA is unique to that ...