This week in science, we learned about the cell cycle.We learned that different cells go through the cycle different amounts of times. The parts of the cycle are- Mitosis, Gap 1, Synthesis, and Gap 2.
We also learned some new vocabulary.
Chromosomes-organized DNA
Chromatids-two chromosomes or sister chromosomes that form an "x" shape
Centriols-create spindle fibbers
Chromatins-unraveled, unorganized DNA
Mitosis happens very quickly. Cells spend 50% of their time in interphase, 27% of their time in prophase, 8% of their time in metaphase, 5% of their time in anaphase, and 2% of their time in telophase. Interphase is not even part of the mitosis process and that is the stage it is in for the longest amount of time.
Many different things are going on during mitosis. During interphase the cell enlarges, the chromosomes replicate, and the centriols replicate. The next part is prophase, this is when the chromosomes condense, the nucleolus disappears, and centriols migrate to the opposite sides. Then prometaphase occurs when the nuclear envelopes, as well as other membranes disintegrate. Next is metaphase where the spindle fibers attach to chromosomes at kinetochores, and chromosomes align on metaphase plates. Now anaphase begins, this is when the spindle fibers shorten, sister chromatids are pulled apart by contracting fibers, and they then move to different poles and the poles move apart. Then telophase starts and the nuclear envelope reforms, the chromosomes disperse, and the spindle fibers dissolve. Now Interphase starts again and the cell has gone through mitosis.
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