Differences Between Mitosis and Meiosis
1. Cell Division
<span><span>Mitosis: A somatic cell divides once. Cytokinesis (the division of the cytoplasm) occurs at the end of telophase. </span><span>Meiosis: A reproductive cell divides twice. Cytokinesis happens at the end of telophase I and telophase II.</span></span>2. Daughter Cell Number
<span>Mitosis: Two daughter cells are produced. Each cell is diploid containing the same number of chromosomes. </span><span>Meiosis: Four daughter cells are produced. Each cell is haploid containing one-half the number of chromosomes as the original cell.</span>3. Genetic Composition
<span><span>Mitosis: The resulting daughter cells in mitosis are genetic clones (they are genetically identical). No recombination or crossing over occur. </span><span>Meiosis: The resulting daughter cells contain different combinations of genes. Genetic recombination occurs as a result of the random segregation of homologous chromosomes into different cells and by the process of crossing over (transfer of genes between homologous chromosomes).</span></span>4. Length of Prophase
<span><span>Mitosis: During the first mitotic stage, known as prophase, chromatincondenses into discrete chromosomes, the nuclear envelope breaks down, and spindle fibers form at opposite poles of the cell. A cell spends less time in prophase of mitosis than a cell in prophase I of meiosis. </span><span>Meiosis: Prophase I consists of five stages and lasts longer than prophase of mitosis. The five stages of meiotic prophase I are leptotene, zygotene, pachytene, diplotene, and diakinesis. These five stages do not occur in mitosis. Genetic recombination and crossing over take place during prophase I.</span></span>5. Tetrad Formation
<span>Mitosis: Tetrad formation does not occur. </span><span>Meiosis: In prophase I, pairs of homologous chromosomes line up closely together forming what is called a tetrad. A tetrad consists of four chromatids(two sets of sister chromatids).</span>6. Chromosome Alignment in Metaphase
<span><span>Mitosis: Sister chromatids (duplicated chromosome comprised of two identical chromosomes connected at the centromere region) align at the metaphase plate (a plane that is equally distant from the two cell poles). </span><span>Meiosis: Tetrads (homologous chromosome pairs) align at the metaphase plate in metaphase I.</span></span>7. Chromosome Separation
<span><span>Mitosis: During anaphase, sister chromatids separate and begin migrating centromere first toward opposite poles of the cell. A separated sister chromatid becomes known as daughter chromosome and is considered a full chromosome. </span><span>Meiosis: Homologous chromosomes migrate toward opposite poles of the cell during anaphase I. Sister chromatids do not separate in anaphase I.</span></span>
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