The first phase is Prophase. In prophase, the chromosomes the chromosomes start to coil, shorten, and become distinct. The nucleoli disappear and each replicated chromosomes appear as the identical sister chromatids join together. The spindle fibers begin to form and it`s made of the centrosomes and the microtubules that extend from …show more content…
The centrosomes are now at opposite ends of the cell. The chromosomes convene on the metaphase plate, an imaginary plane that is equidistant between the spindle`s the poles. The chromosomes centromeres lie on the metaphase plane. Each chromosome, the kinetochores of the sister chromatids are attached to kinetochore microtubules coming from the opposite poles. A cell cannot enter anaphase unless all the chromosomes have aligned themselves. The line in which the chromosome line up is called the spindle equator. When metaphase is completed, the cell moves to …show more content…
Two daughter nuclei form in each daughter cell, forming nuclear envelopes around each nucleus. There are two theories as to how this happens: vesicle fusion-when fragments of the nuclear membrane fuse to rebuild the nuclear membrane. Reshaping of the endoplasmic reticulum-where the parts of the ER containing absorbed nuclear membrane envelop the nuclear space, reforming closed membrane. The chromosomes are become less condensed. As the nuclear membranes re-form around each set of chromatids, the nucleoli also reappear. The chromosomes also unwind back into the expanded chromatin that is present during interphase. Telophase accounts for approximately 2% of the cell cycle 's duration. Chromosomes are uncoiled from spindle fibers and lengthened. Spindle fibers degenerate. The division of one nucleus into toe genetically identical nuclei, is now