Cell Cycle - the cell cycle is a series of events from the time a cell first form until the cytoplasm divides. Breaks can occur on the cell cycle that keeps the majority of the cells in the G1 phase. Checkpoint genes are a mutation that effects the cell cycle. A cell loses control over the cell cycle when a certain amount of checkpoint mechanisms fail. The cell cycle produces two daughter cells.
The Cell Cycle
Interphase - the interval between mitotic divisions when a cell grows. During interphase, cells replicate their DNA and double the amount of its cytoplasmic components. Typical cells spend most of their lives in interphase. The three stages of interphase are G1, the stage in which cells grow, S, the stage in which DNA is doubled, and G2, the stage in which are checkpoints for protein synthesis needed for cell division. During interphase, chromosomes are loosened to allow DNA replication and transcription to occur. Cells can skip interphase. It is a resting phase.
Prophase - the early stages of prophase consist of preparation for nuclear division so the chromosomes begin to pack tightly. It is the first phase of cell division and it occurs before metaphase. During prophase chromosomes become visible as paired chromatids and this causes the nuclear envelope to disappear.
Metaphase - one of the final stages of mitosis. Is when all chromosomes are aligned midway between spindle poles. It is the second stage of cell division and during metaphase, chromosomes bind to the spindle poles.
Anaphase - one of the final stage of mitosis. Is when sister chromatids separate and move toward opposite spindle poles. By the end of it, small microtubules form on either side of the future plan of division. Cytokinesis occurs towards the end of this phase.
Telophase - is one of the final stages of mitosis and the final stage of cell division. Is when chromosomes arrive at opposite spindle poles and decondense and two new nuclei form as a result. Cytokinesis occurs at the end of this phase. This is when the spindle begins to disassemble.
Telomeres - non coding repeat DNA sequences that are found at the ends of eukaryotic chromosomes. They repeat thousands of times. Cell divisions that are dependent upon telomeres may protect against uncontrolled cell division. It is a region of repetitive nucleotide sequences at the end of each separate chromosome.
Cancer - its cells most commonly consist of high numbers of telomerase. It is a very deadly diesease that causes 15 to 20 percent of human deaths in developed countries. It is a diesease in which abnormal cells divide and then tear apart the body's tissue.