The Cell Cycle is a critical process in which Eukaryotic cells grow and divide throughout a series of events. The first phase, Interphase takes up around 90% of the cell’s life.
This stage has substages including G1, synthesis (S phase), and G2. G1(“Gap 1”) is the stage of growth in which the cell grows larger, makes new proteins, and develops organelles. Next is synthesis, defined by DNA replication.
DNA, composed of genes, is first unzipped by the helicase (an enzyme) by breaking up the hydrogen bonds. Afterwards, the DNA polymerase adds nucleotides to match with the parent DNA strand (adenine to thymine, guanine to cytosine), checking for any errors. The helicase then winds the DNA strands back together, creating two new DNA strands.
G2, the last phase before Mitosis, prepares the cells for the next stage by producing structures necessary. Lastly is Mitosis, the shortest phase. The nucleus is divided, distributing DNA copies into the daughter cells, which can be done through mitosis, subdivided into four phases: prophase, metaphase, anaphase, and telophase. During Prophase, the nuclear envelope dissolves as centrioles in the cytoplasm begin to move to opposite poles of the cell. In the Metaphase, chromosomes (tightly packed chromatin) are moved to line up at the center. In Anaphase, the sister chromatids are detached by the spindle fibers at the kinetochores and continue to move towards opposite sides of the cell. Finally, the Telophase is evident as the chromosomes are no longer visible to the naked eye as well as a pinch in the center of the cell. The very last phase is cytokinesis, the division of the cytoplasm, making the two daughter cells.
After the completed process, the daughter cells go through Interphase, repeating cell cycle once again. If the Cell Cycle has any disruptions, it can lead to many diseases and mutations that can be deadly. The most known result of disruptions in the cycle would be cancer, which is the rapidly uncontrolled growth of cells.