31. In anaphase also, the microtubules attached to the chromosomes maintain a carefully regulated shortening and lengthening process. 32. During the pre-anaphase stage, cleavage furrows are formed in the spermatocyte cells containing four univalent chromosomes. 33. The spindle checkpoint system is a regulatory system that restrains progression through the metaphase-to-anaphase transition. 34. Without Cdc20, the anaphase -promoting complex ( APC ) cannot become activated and anaphase is not triggered. 35. Without Cdc20, the anaphase-promoting complex ( APC ) cannot become activated and anaphase is not triggered. 36. It is required for two microtubule-dependent processes : nuclear movement prior to anaphase , and chromosome separation. 37. The checkpoint is held active by any unattached centromere; only when all centromeres are attached will anaphase commence. 38. During mitosis, there are four stages of cell division : Prophase, Metaphase, Anaphase , and Telophase. 39. FEAR ( Cdc Fourteen Early Anaphase Release ) complex proteins, SLK19 and SPO12 regulate the release of Cdc14. 40. The presence of this positive feedback loop offers a potential mechanism for giving anaphase a more switch-like behavior.
