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MITOSIS,  It is the division of parent cell in to 2-identical daughter cell, having the same no. & kind of chromosomes also known as, equational cell division.,  It was 1st discovered by E.strasburger in plant cell, & by W., flemming in animal cells.,  The term mitosis was coined by W.Flemming.,  It occurs in somatic cell of living organism & in plant cell it, occurs in meristamatic tissue.,  The process of mitosis is basically completed in 2-stages,, Karyokinesis & Cytokinesis, Karyokinesis:,  It is the division of nucleus completed in 4-stages., Prophase, Metaphase, Anaphase, Telophase, Prophase:,  It is the longest stage of M-phase.,  It occurs after G2-phase of I-phase. This phase begins the, chromatin fiber start condensing and the chromosome start, appearing as fine thread.,  They look like a loose ball of wool. Hence this stage also, called as sprime stage.,  The chromosomes are split longitudinally to form two, chromatids each. Both the chromatids are however, associated at the centromere region., , In the final stage the nuclear membrane and nucleolus, disappear and chromosomes are found in cytoplasm.,  In plant due to the complete absence of centriole no astral, arrangement is seen and hence the spindle is called anastral, spindle.,  In animal cells the spindle fibers are attached to the Astral, Ray at both the poles hence in animal cells the spindle fiber, is called Amphi-astral., , , Metaphase:,  This phase begins with the complete disappearance of the, nuclear membrane.,  The chromosomes get themselves arranged at the Central, part of the cell on the equatorial portion.,  The spindle fiber which extends from one pole to another, of the cell is called as continuous spindle fiber and the, spindle fiber which do not extend are called as, discontinuous spindle fiber.,  The discontinuous spindle fiber attached them to the, centromere of chromosome and their contraction pulls the, chromosomes and arranges them on the equator of the cell, known as congration.,  The centromeres of the chromosome lie on the equatorial, line of the cell and form the metaphasic plate., Anaphase:,  It is the shortest and fastest phase of metaphase.,  During early anaphase division of centromere takes place.,  Both chromatids of the chromosome separate from each, other and separated chromatids are called daughter, chromosomes.

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 During late anaphase daughter chromosomes move to their, respective pole due to contraction, expansion of continuous, spindle fiber.,  Shapes of chromosome are observed in anaphase like V, L, J, or I.,  In plant cell cytokinesis also starts in late anaphase., Telophase:,  Here all events are reverse of prophase hence is called, reverse Prophase.,  The daughter chromosomes which have reached the, opposite poles of the cell now become straight.,  The spindle fibers disappear. Nuclear membrane and, nucleolus reappear at both the poles.,  Hydration and de-condensation of chromosome text place.,  At the end of this phase the parent cell is divided into two, halves by the formation of cell plate., Significance of Mitosis:,  It helps in producing to genetically identical cells.,  In unicellular organisms it increases the number of, individuals.,  In multicellular organisms it is responsible for the growth of, body d and repairing off body part.,  Uncontrolled Mitosis causes cancer., , Cytokinesis:,  In plant cell the end of telophase the division of cytoplasm, of the daughter cell formed. The spindle region of a dividing, , cell after the chromosomes have moved to the poles is, called phragmoplast. It gives in to two identical daughter, cells.,  In animal cell cytokinesis takes place by cell furrow method.