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  • Essay / Comparison of Mitosis and Meiosis

    Mitosis and meiosis are both forms of cell division, however, their processes are not identical. Mitosis occurs in somatic cells (cells that are not gametes) and produces two genetically identical daughter cells. Mitosis replaces dead or damaged cells or during growth. Mitosis consists of 4 phases: prophase, metaphase, anaphase and telophase. DNA replication occurs during S phase, which precedes the mitotic phase. During prophase, chromatin condenses into chromosomes and the mitotic spindle forms (textbook, 94). During metaphase, the chromosomes line up in the middle of the cell, called the metaphase plate. During anaphase, pairs of chromatids separate and each half of the pair is called a chromosome. During telophase, the final stage of mitosis, identical sets of chromosomes are at opposite poles of the cell, the chromosomes return to chromatin, and a nuclear envelope reforms around each group of chromatin. The division of the cytoplasm after nuclear division is called cytokinesis (textbook, 95).Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”?Get the original essayMeiosis, on the other hand, occurs in gametes (sex cells), produces four genetically different daughter cells, and involves two divisions of genetic material. Meiosis is divided into two parts: meiosis I and meiosis II, both consisting of four parts. Meiosis I first occurs after DNA replication and includes prophase I, metaphase I, anaphase I, and telophase I. Prophase I, much like the prophase of mitosis, occurs when the chromosomes shorten and the mitotic spindle forms. However, unlike prophase of mitosis, the two genetically identical sister chromatids pair up and crossover occurs between non-sister chromatids. Crossbreeding is the very important reason why no two people have the same DNA. Metaphase I is very similar to the metaphase of mitosis because homologous pairs of chromosomes line up along the metaphase plate. In anaphase I, homologous pairs of chromosomes are separated and pulled toward opposite sides of the cell, leaving the paired chromatids still together (textbook, 97). Meiosis I gives rise to two genetically different haploid cells after telophase I and cytokinesis which are similar to telophase. and mitotic cytokinesis. Meiosis II includes prophase II, metaphase II, anaphase II, and telophase II. Prophase II is similar to prophase in mitosis and no crossover occurs during prophase II. Metaphase II occurs when sister chromatids align along the metaphase plate. During anaphase II, sister chromatids separate and move toward opposite poles of the cell. The final stage of meiosis is telophase II and cytokinesis where the nuclear envelopes reform and four genetically different haploid gametes are formed following the original single diploid cell (textbook, 97). Works Cited Campbell, NA, Urry, LA, Cain, ML, Wasserman, SA, Minorsky, PV, & Jackson, RB (2018). Biology (12th ed.). Pearson. Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2007). Molecular biology of the cell (5th ed.). Garland Science. Sadava, D., Hillis, DM, Heller, HC, and Berenbaum, MR (2016). Life: The Science of Biology (11th ed.). WH Freeman. Lodish, H., Berk, A., Kaiser, CA, Krieger, M., Scott, MP, Bretscher, A., ... and Matsudaira, P. (2003). Molecular Cell Biology (5th ed.). WH Freeman. Purves, WK, Sadava, D., Orians, GH and Heller, HC (2004). The life :.