Meiosis

• Meiosis is a type of cell division that occurs in sexually reproducing organisms. It involves two rounds of division, but only one round of DNA replication.
• Meiosis results in four haploid cells (half the chromosomes of a regular, or diploid cell).

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1. Interphase: Chromosomes replicate, the same as mitosis.

2. Meiosis I: Meiosis I is very similar to that of Mitosis. The result of Meiosis I is two daughter diploid cells with chromatids that include region of nonsister DNA, which produces genetic variation.

• Prophase I: The chromosomes are in synapsis, which means they are held together by proteins, and go through the process of crossing over. Crossing over is the process of exchanging segments of DNA of the nonsister chromatids.
• Metaphase I: The chromosomes align themselves in the center of the cell, still in their homologous pairs.
• Anaphase I: The chromosomes separate and are drawn to the poles, with the sister chromatids still attached to one another.
• Telophase I and Cytokinesis: Two distinct haploid cells are formed. The reason these two stages are grouped together is because they occur at the same time. In animal cells, a cleavage furrow forms, and in plant cells, a cell plate forms.

Notice how the chromosomes exchange DNA in crossing over during meiosis I.
Click image to be taken to the source.

3. Meiosis II: The result of Meiosis II is two haploid cells from each diploid cell created in Meiosis I, forming a total of four distinct daughter cells from the original cell. The haploid cells are distinct due to the crossing over in Prophase I, and each cell has only half the cells of the original cell (the definition of haploid). 

• Prophase II:  There is not a lot of movement in this stage, as sister chromatids are already paired up from Meiosis I. Notice that there is not another interphase, no DNA replication occurs between Meiosis I and Meiosis II.
• Metaphase II:  Chromosomes align themselves at the center of the cell. Sister chromatids are not genetically identical anymore due to the crossing over actions in Prophase I.
• Anaphase II:  Chromatids separate and move towards opposite poles.
• Telophase II and Cytokinesis:  The nuclear envelope starts to reappear, and cytokinesis occurs as it usually does in Meiosis I and Mitosis.

Notice the resulting four daughter cells of meiosis II each have unique DNA segments.
Click image to be taken to the source.

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It is important to remember that four daughter cells are produced, versus the two produced in mitosis. The crossing over that occurs during meiosis makes each daughter cell unique. In addition, the same process of cell division occurs in each division, and the division is similar to that of mitosis. Chromosomes are only replicated once, and one diploid cell produces four haploid cells.

To review the cell cycle, mitosis, meiosis, and the distinction between sexual and asexual reproduction, bozemanbiology on YouTube has a great video (x):