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3 Nucleolus & nuclear membrane reappears. 1 1 ‘, , Cytokinesis-It starts when the telophase is in progress.in plant cell cytokinesis is by cell plate formation, &in animal cell itis by furrow formation. The vesicles & tubules comes from golgibodies accumulates at the, equator and fuses to form the cell plate. Soon the cellplate act as the middle lamellae.Upon the middie _, lamellae cellulose fibrils deposite to form cell wall. a, , Biological significance of mitosis., , 1 It is responsible for growth & development in organisms body. =, , , , 2. It maintains the quantitative & qualitative distribution of hereditary material to the daughter cells., , 3.Cell repair mechanism is brought about by mitosis., , , , 4. It play an important role in asexual reproduction in organisms., , Meiosis-The division of germ cell or reproductive cell is said to be meiosis.|t was first observed by, Strasberger (1888) A diploid cell undergoes meiosis and produces four haploid cells. Meiosis involves two, cell divisions, meiosis | &meiosis II. Each division is further sub divided in to Prophase , Metaphase, ,Anaphase &Telophase., , Meiosis [-In this stage reduction in the chromosome number takes place. So meiosis is also known as :, reduction division. It involves the following sub stages., , Prophase I- it is of the longest duration & it is sub divided in to 5 sub stages as follows., 1. Leptotene, *Chromosomes appears as thin threads with centromere &becomes gradually visible under light, microscope., , *Nucleolus & nuclear membrane are intact., 2. Zygotene, *Members of each pair of hohologous chromosomes(paternal& maternal) starts pairing. This process, pairing is called synapsis. 3 ee