Under our experimental conditions (22-23 °C with plenty of food), the cell cycle of Aspidisca aculeata, stock Ge1, lasts 9 hrs. The macronuclear phases G1, S, G2 and D occupy 58%, 34%, 3%, 5%, respectively, of the cell cycle. The micronuclear cycle is characterized by the absence of the G2 phase as the S phase is followed immediately by the micronuclear division which precedes the macronuclear one. The length of micronuclear phases, G1, S and D corresponds, respectively, to 87%, 5%, 8% of the cell cycle. When more micronuclei are present in the same cell, they divide asynchronously.
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Con il contributo del Ministero per i Beni e le Attività Culturali