FIGURE 9.9 Fluorescent sequencing chemistries. Dye primer sequencing uses labeled primers (left). The reactions take place inseparate tubes and the products of all four reactions are resolvedtogether in one lane of a gel or in a capillary. Using dye termina-tors (right), only one reaction tube is necessary because the fragments can be distinguished directly by the dideoxynucleotides on their 3 ′ ends.