Help! I’m totally lost with meiosis phases in bio class
Hi everyone, I’m preparing for my biology exam and I’m really struggling to understand the phases of meiosis. There are so many steps and names like prophase, metaphase, anaphase… I mix everything up between meiosis I and II. Can someone please explain in simple words what happens in each main phase and why there are two divisions instead of one like in mitosis? I would really appreciate a clear summary because my textbook is too complicated.
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Here is a good explanation of the phases of meiosis. Meiosis has two big parts — Meiosis I and Meiosis II. It starts with one diploid cell (2n) that has already copied its DNA. In Meiosis I homologous chromosomes pair up and crossing over happens (very important for genetic variation!). Then in metaphase I the pairs line up in the middle, and in anaphase I the homologous chromosomes are pulled apart to opposite sides. After telophase I and cytokinesis you get two haploid cells (n), but each chromosome still has two chromatids. Meiosis II is very similar to mitosis: no more pairing, chromosomes line up singly in metaphase II, sister chromatids separate in anaphase II, and finally you have four different haploid gametes (sperm or eggs). The main purpose is to reduce chromosome number by half and create genetic diversity through crossing over and independent assortment. This process is essential for sexual reproduction and evolution. Without it, chromosome number would double every generation.