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      <title>Unit 4 Assignment by </title>
      <link>https://padlet.com/lindseymcbeth/yy8t583gp3uvlf7h</link>
      <description>Mitosis and Meiosis</description>
      <language>en-us</language>
      <pubDate>2024-05-26 19:52:26 UTC</pubDate>
      <lastBuildDate>2024-05-29 04:34:39 UTC</lastBuildDate>
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         <title>Mitosis and Its Phases</title>
         <author>lindseymcbeth</author>
         <link>https://padlet.com/lindseymcbeth/yy8t583gp3uvlf7h/wish/3007732864</link>
         <description><![CDATA[<p>Mitosis consists of five stages: </p><ol><li><p>Prophase: Prophase, the longest stage of mitosis, involves several critical events: the nuclear membrane breaks down into vesicles, the nucleus disintegrates, and the centrosome duplicates and moves to opposite cell ends. These centrosomes organize microtubules into spindle fibers, forming the mitotic spindle. Meanwhile, chromosomes condense into visible structures, each consisting of two sister chromatids connected by a centromere.</p></li><li><p>Prometaphase: During metaphase, chromosomes, guided by their centromeres, move to the cell's equatorial plane, forming the metaphase plate. Spindle fibers attach to the kinetochores on each side of the centromeres, ensuring proper alignment. The chromosomes further condense during this stage.</p></li><li><p>Metaphase: The chromosomes align along the spindle apparatus's metaphase plate.</p></li><li><p>Anaphase: Anaphase, the shortest stage of mitosis, involves the division of centromeres and the separation of sister chromatids, which are pulled to opposite cell ends by spindle fibers attached to kinetochores. These separated chromatids are now called daughter chromosomes. This process ensures that each daughter cell receives an identical set of chromosomes.</p></li><li><p>Telophase: Telophase, the final stage of mitosis, reverses prophase processes: the nuclear membrane reforms around chromosomes at each pole, chromosomes uncoil, and spindle fibers disappear. During cytokinesis, the cell divides into two new cells: a cell plate forms in plants, while in animals, the cytoplasm constricts. The cell then enters interphase, the period between mitotic divisions (<em>The Cell Cycle, Mitosis and Meiosis for Higher Education</em>, 2020).</p></li></ol><p>Image Source: <em>The cell cycle, mitosis</em>,<em> and meiosis for higher education</em>. (2020, October 26). University of Leicester. <a rel="noopener noreferrer nofollow" href="https://le.ac.uk/vgec/topics/cell-cycle">https://le.ac.uk/vgec/topics/cell-cycle</a></p>]]></description>
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         <pubDate>2024-05-26 20:06:26 UTC</pubDate>
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         <title>The Two Types of Meiosis</title>
         <author>lindseymcbeth</author>
         <link>https://padlet.com/lindseymcbeth/yy8t583gp3uvlf7h/wish/3011149390</link>
         <description><![CDATA[<p>Meiosis is the process by which diploid cells produce haploid gametes through one round of DNA replication followed by two cell divisions (Meiosis I and II).</p><p>Meiosis I:</p><p>- <strong>Prophase I</strong>: Chromosomes condense, homologous chromosomes pair and exchange DNA (crossing over), forming recombinant chromosomes. It includes five phases: leptotene, zygotene, pachytene, diplotene, and diakinesis.</p><p>- <strong>Prometaphase I</strong>: Spindle apparatus forms, chromosomes attach to spindle fibers.</p><p>- <strong>Metaphase I</strong>: Homologous chromosome pairs align randomly along the metaphase plate, contributing to genetic variation.</p><p>- <strong>Anaphase I</strong>: Homologous chromosomes separate and move to opposite poles.</p><p>- <strong>Telophase I</strong>: Chromosomes diffuse, nuclear membrane reforms.</p><p>- <strong>Cytokinesis</strong>: Cell divides, resulting in two haploid cells.</p><p>### Meiosis II:</p><p>- <strong>Prophase II</strong>: Chromosomes condense, nuclear membrane dissolves, spindle fibers form.</p><p>- <strong>Metaphase II</strong>: Chromosomes line up in the center of the cell.</p><p>- <strong>Anaphase II</strong>: Centromeres divide, sister chromatids move to opposite poles.</p><p>- <strong>Telophase II</strong>: Chromosomes reach opposite ends, nuclear membrane reforms.</p><p>- <strong>Cytokinesis</strong>: Cell division results in four sperm cells in males or three polar bodies and one mature egg in females.</p><p>Meiosis generates genetic diversity through crossing over in Prophase I, random alignment of homologous chromosomes in Metaphase I, and random alignment of sister chromatids in Metaphase II.</p><p><br></p><p>Text Source: <em>The cell cycle, mitosis and meiosis for higher education</em>. (2020, October 26). University of Leicester. <a rel="noopener noreferrer nofollow" href="https://le.ac.uk/vgec/topics/cell-cycle">https://le.ac.uk/vgec/topics/cell-cycle</a></p><p>Image Source: Mukherjee, S. (2023, May 16). <em>Meiosis: Definition, Stages, &amp; Purpose with Diagram</em>. Science Facts. <a rel="noopener noreferrer nofollow" href="https://www.sciencefacts.net/meiosis.html">https://www.sciencefacts.net/meiosis.html</a></p>]]></description>
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         <pubDate>2024-05-29 04:25:32 UTC</pubDate>
         <guid>https://padlet.com/lindseymcbeth/yy8t583gp3uvlf7h/wish/3011149390</guid>
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      <item>
         <title>Mendel&#39;s Law of Independent Assortment of </title>
         <author>lindseymcbeth</author>
         <link>https://padlet.com/lindseymcbeth/yy8t583gp3uvlf7h/wish/3011154396</link>
         <description><![CDATA[<p>The behavior of chromosomes during meiosis generates genetic variation through two key processes:</p><ol><li><p><strong>Crossing Over (Prophase I)</strong>:</p><ul><li><p>Homologous chromosomes pair up and exchange genetic material, forming recombinant chromosomes. This results in new combinations of alleles on each chromosome (Pierce, 2017).</p></li><li><p>The formation of chiasmata (points where chromosomes crossover) ensures that each gamete contains a mix of maternal and paternal genes (Lodish et al., 2016).</p></li></ul></li><li><p><strong>Independent Assortment (Metaphase I)</strong>:</p><ul><li><p>Homologous chromosome pairs align randomly along the metaphase plate. This random alignment means that the orientation of each pair is independent of others (Hartwell et al., 2014).</p></li><li><p>The random separation of these homologous pairs into daughter cells leads to a unique combination of chromosomes in each gamete (Pierce, 2017).</p></li><li><p>Mendel's law of independent assortment is explained by this process, as the distribution of one pair of homologous chromosomes does not affect the distribution of another pair, resulting in a variety of possible genetic combinations (Griffiths et al., 2015).</p></li></ul></li></ol><p>Image and Text Source: Sapkota, A. (2023, August 3). <em>Mendel's Law of Independent Assortment- Definition, Examples, Limitations</em>. Microbe Notes. <a rel="noopener noreferrer nofollow" href="https://microbenotes.com/mendels-law-of-independent-assortment/">https://microbenotes.com/mendels-law-of-independent-assortment/</a></p>]]></description>
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         <pubDate>2024-05-29 04:29:59 UTC</pubDate>
         <guid>https://padlet.com/lindseymcbeth/yy8t583gp3uvlf7h/wish/3011154396</guid>
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