Week 1 Reflection

This week we learned about the process of meiosis. Meiosis is a reduction division that creates 4 genetically different, haploid daughter cells. Meiosis is much like mitosis in that the cell goes through prophase, metaphase, anaphase, and telophase. However, meiosis goes through these steps twice, having eight steps instead of four. It contains two divisions, meiosis I and meiosis II. In prophase I, the chromosomes replicate, and find their homologous chromosome to form a tetrad. Homologous chromosomes means chromosomes that code for the same gene. When they pair up, they may exchange genes. The process of exchanging genes is called crossing over. The tetrads line up at the center in metaphase I, and the homologous chromosomes are pulled apart in anaphase I. Two new diploid, daughter cells are formed through meiosis I. Before the cells undergo meiosis II, the DNA does not replicate. The chromosomes line up at the center of the cell in metaphase II, and the sister chromatids are pulled apart in anaphase II. Four daughter cells are now formed and become gametes. The cells are haploid and all are genetically different causing no one offspring to be identical. The gametes created in males are called sperm, and in females they are called eggs. In males, all four of the created cells develop into sperm, while in females only one cell becomes the egg, and the others support that egg.

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