The cell cycle describes the sequence of events that occurs during the life of most eukaryotic cells. Cell division consists of two phases, nuclear division followed by cytokinesis. Nuclear division divides the genetic material in the nucleus, while cytokinesis divides the cytoplasm. There are two kinds of nuclear division—mitosis and meiosis. Mitosis divides the nucleus so that both daughter cells are genetically identical. In contrast, meiosis is a reduction division, producing genetically variable daughter cells that contain half the genetic information of the parent cell.
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Mitosis and Cytokinesis
In prophase, nucleoli disappears and chromatin condenses.Mitotic spindles that help to drag the chromosomes to opposite poles appears.
In metaphase, chromosomes are distributed along the equator of the cell. Spindle fibers are attached to the centromere of the chromatid. Each chromatid has four arms.
In anaphase microtubules attached to centromere pull each chromosome towards opposite poles.Chromatids condense and are now known as chromosomes. At the end of this stage each pole contain same number of chromosomes as parent cell.
Telophase concludes the nuclear division.A nuclear membrane develops around each pole forming two nulcei.The chromosomes disperse into chromatin and nucleoli reappear again.
Mitosis is followed by cytokinesis, which divides the cytoplasm into two. In plant cells golgi complex moves between the newly forming nucleus and become the plasma membrane of the cells. Cell wall is forms on top of plasma membranes.
In animal cells, microtubules help in forming a structure called cleavage furrow, which helps I the division of cytoplasm.
Growth phase: Once mitosis and cytokinesis are completed cell enters growth phase. This growth period is divided into three phases, designated G1, S, and G2 to distinguish special activities that occur.
Courtesy:Cliff's AP Biology