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Cytokinesis (/ ˌ s aɪ t oʊ k ɪ ˈ n iː s ɪ s /) is the part of the cell division process and part of mitosis during which the cytoplasm of a single eukaryotic cell divides into two daughter cells. Cytoplasmic division begins during or after the late stages of nuclear division in mitosis and meiosis.
The eukaryotic cell cycle consists of four distinct phases: G 1 phase, S phase (synthesis), G 2 phase (collectively known as interphase) and M phase (mitosis and cytokinesis). M phase is itself composed of two tightly coupled processes: mitosis, in which the cell's nucleus divides, and cytokinesis, in which the cell's cytoplasm and cell membrane divides forming two daughter cells.
The phragmoplast is a microtubule structure typical for higher plants, whereas some green algae use a phycoplast microtubule array during cytokinesis. [39]: 64–7, 328–9 Each daughter cell has a complete copy of the genome of its parent cell. The end of cytokinesis marks the end of the M-phase.
In animals the cytokinesis ends with formation of a contractile ring and thereafter a cleavage. But in plants it happen differently. At first a cell plate is formed and then a cell wall develops between the two daughter cells. [36] In Fission yeast the cytokinesis happens in G1 phase. [37]
Cytokinesis typically begins before late telophase [1] and, when complete, segregates the two daughter nuclei between a pair of separate daughter cells. Telophase is primarily driven by the dephosphorylation of mitotic cyclin-dependent kinase (Cdk) substrates.
The G1/S transition, more commonly known as the Start checkpoint in budding yeast (the restriction point in other organisms) regulates cell cycle commitment. [1] At this checkpoint, cells either arrest before DNA replication (due to limiting nutrients or a pheromone signal), prolong G1 (size control), or begin replication and progress through ...
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The cell cycle begins with interphase when the DNA replicates, the cell grows and prepares to enter mitosis. Mitosis includes four phases: prophase , metaphase , anaphase , and telophase . Prophase is the initial phase when spindle fibers appear that function to move the chromosomes toward opposite poles.