Cell Science and Molecular Biology

Cell Cycle and Cell Division

The cell cycle is a highly regulated process that controls the growth and division of cells. It consists of several distinct phases, including interphase (G1, S, and G2 phases) and mitosis (prophase, metaphase, anaphase, and telophase), each of which is characterized by specific events and activities. Cell division, or cytokinesis, occurs at the end of the cell cycle and results in the formation of two daughter cells from a single parent cell. The cell prepares for division by growing in size (G1 phase), replicating its DNA (S phase), and continuing to grow and prepare for division (G2 phase). Chromatin condenses into chromosomes, the nuclear envelope breaks down, and the mitotic spindle forms. Chromosomes align at the metaphase plate, a plane equidistant from the two spindle poles. Sister chromatids separate and move toward opposite spindle polesThe cell cycle is regulated by a complex network of regulatory proteins, including cyclins and cyclin-dependent kinases (CDKs), which control the progression through each phase of the cycle. Dysregulation of the cell cycle can lead to uncontrolled cell division and is associated with various diseases, including cancer.