FIGURE 19-20 Chromosome attachment to the mitotic spindle. Chromosomes attach to the mitotic spindle and assemble at the spindle center. They then attach, via their kinetochores, to the ends of microtubules (called end-on attachments), and these attachments are stabilized by additional microtubules. The final chromosome attachment, in which the chromosome is stably bi-oriented on the mitotic spindle, is shown. “(−) end” indicates the minus end of the microtubule, “(+) end” the plus end.