Biology Homework Help – Stuck on Meiosis!
Hi everyone, I’m really confused about meiosis for my biology test tomorrow. Can someone explain what happens in each step? I know there are two divisions, Meiosis I and Meiosis II, but I mix up the phases like prophase, metaphase and all that. Why do we need crossing over? And how many cells do we get at the end? Please help, I need clear simple explanation.
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Meiosis is the process that makes sperm and egg cells with half the chromosomes. It has two main parts: phases of meiosis I and II.Basically: Before meiosis starts, DNA replicates. Then in Meiosis I homologous chromosomes pair up, crossing over happens (this mixes maternal and paternal genes = genetic variation), then homologues separate so each daughter cell gets one from each pair. After that Meiosis II is like mitosis – sister chromatids separate. In the end you get four different haploid cells. Crossing over is very important because it creates new combinations of genes, which helps evolution and makes every person genetically unique (except identical twins). The main phases are: Prophase I (longest, crossing over here), Metaphase I, Anaphase I, Telophase I → then Prophase II, Metaphase II, Anaphase II, Telophase II. After cytokinesis you have 4 haploid gametes. Hope this helps!