The Cell Cycle: A Fundamental Biological Process Cell cycle is a sequence of events the cell undergoes while it is proliferative and dividing. It is a basic process of life of all organisms. The cell cycle consists of two major phases: Interphase: Interphase: G1 Phase (Gap 1): This is a period of cell growth and activity. The cell grows bigger and produces proteins and organelles. S Phase (Synthesis): In this phase, DNA replication takes place, doubling the amount of genetic material. G2 Phase (Gap 2): The cell keeps to grow and to get ready before dividing. M Phase (Mitotic Phase): M Phase (Mitotic Phase): Mitosis: This is the process of nuclear division in which replicated chromosomes are segregated to two daughter nuclei. It involves four stages: Prophase: Chromosomes condense and become visible. Metaphase: Chromosomes align at the metaphase plate. Anaphase: Sister chromatids separate and move towards opposite poles. Telophase: 1 Nuclear envelopes form around the separated chromosomes. 1.  Cytokinesis: División de la citoplasma que produce dos células hijas. Regulation of the Cell Cycle: Regulation of the Cell Cycle: The cell cycle is effectively controlled by a network of interacting proteins, including cyclins and cyclin-dependent kinases (CDKs). By these proteins all the stages of the cell cycle are properly managed and cell division only occurs if it is necessary. Checkpoints: Checkpoints: The cell cycle contains various checkpoints that check its progression and guarantee that the cell is prepared to go to the next stage. The major checkpoints are: G1 Checkpoint: Predicts whether the cell will enter the S phase. G2 Checkpoint: Confirms completion of DNA replication and that the cell is ready for mitosis. Metaphase Checkpoint: Confirms that each chromosome is correctly positioned at the metaphase plate. Abnormalities of the cell cycle, for example, result in severe, potentially cancerous, consequences. Cell cycle understanding is the cornerstone of cell proliferation, development, and disease.