Figure 7.

In situ analysis of cell cycle. A and B show changes with time in the duration of the cell cycle, as calculated in Equation 9, in leaves 8 (left) and 16 (right) and in zones drawn on the lamina of both leaves. C and D show changes with time in the percentage of nuclei in the S-G2-M phase analyzed by flow cytometry. E and F show changes with time in the duration of the S-G2-M phase as calculated in Equation 13. Symbols are as in Figure 3. The oblique dotted lines in A and B represent the times that remain available before completion of division in the base of the leaf. When duration of the cell cycle exceeds this limit, a mean cell in zone B will not have time to complete its cycle. Intervals of confidence at 0.95 are presented for flow-cytometry data.