Often referred to as the “cell-division cycle”, this describes the events that take place in a cell, leading to its division and duplication of DNA to produce two “daughter cells”. It can be quite complicated when explored in-depth, but its main steps are: Interphase (Chromosomes are extended and used in the G1, S, and G2 phases), Prophase (Chromosomes condense, nuclear envelop breaks down, and the spindle forms), Metaphase (Chromosomes line up on the central plane of the cell), Anaphase (Centromeres divide, chromatids move towards opposite poles), Telophase (Chromosomes uncoil, new nuclear envelope forms. Spindle fibers disappear), and finally Cytokinesis (Cytoplasm of cell is cleaved in half).
The cell cycle is the sequence of events that a cell goes through as it grows, replicates its DNA, and divides into two daughter cells. The cell cycle can be divided into two main phases: interphase and mitosis.
Interphase is the longest phase of the cell cycle and can be further divided into three stages: G1 (gap 1), S (synthesis), and G2 (gap 2). During G1, the cell grows and performs normal metabolic functions. During the S phase, DNA replication occurs, resulting in the duplication of the cell’s genetic material. During G2, the cell prepares for mitosis by synthesizing proteins and organelles needed for cell division.
Mitosis is the second phase of the cell cycle and is responsible for the actual division of the cell into two daughter cells. Mitosis is divided into four main stages: prophase, metaphase, anaphase, and telophase. During prophase, the chromatin condenses into visible chromosomes, the nuclear envelope breaks down, and spindle fibers begin to form. During metaphase, the chromosomes line up along the equator of the cell. During anaphase, the sister chromatids separate and move toward opposite poles of the cell. During telophase, the nuclear envelope reforms around the two sets of chromosomes, and the cell divides into two daughter cells through a process called cytokinesis.
The cell cycle is tightly regulated by a variety of internal and external factors, including checkpoints that ensure that the cell progresses through each phase of the cycle in the correct order and at the appropriate time. When the cell cycle is disrupted, it can lead to uncontrolled cell growth and the development of cancer.