FIGURE 19-4 The fission yeast S. pombe. (a) Scanning electron micrograph of S. pombe cells at various stages of the cell cycle. Long cells are about to enter mitosis; short cells have just passed through cytokinesis. (b) Main events in the S. pombe cell cycle. START is the point in the cell cycle after which cells are irreversibly committed to cell division. As in S. cerevisiae, the nuclear envelope does not break down during mitosis.

[Part (a) Steve Gschmeissner/Science Source.]