Fig. 6. Developmental regulation of the cell cycle. (A) Live-cell measurements of lengths of M, early and late S phases in growing (growth), 3-hour developed (3 hrs) and slug cells. Bars indicate s.d. (B) Developmental variation in the proportion of the population in late S phase. Snapshots were collected of cells at different stages in development, using disaggregated cells for multicellular stages. Bars represent s.d. (C) Reconstructed image of an intact slug showing S-phase distribution. S-phase cells are abundant in the middle and posterior of slugs (prespore fate). Few S-phase cells are observed in the anterior of slugs (prestalk fate). (D) Effects of nutrition on cycle phases. Cells were cultured in standard imaging media (25% HL5/75% LF), bacterial and glucose-free media (25% HL5/75% LF without glucose).