Unit 3.2-Chp 11-4 Meiosis (Jamie Scott's conflicted copy...
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Transcript of Unit 3.2-Chp 11-4 Meiosis (Jamie Scott's conflicted copy...
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Before meiosis I, each chromosome is replicated.
Prophase I, Metaphase I, Anaphase I, Telophase I
Prophase of meiosis I - each chromosome pairs with its corresponding homologous chromosome to form a structure called a tetrad
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As homologous chromosomes pair up and form tetrads in meiosis I, they exchange portions of their chromatids in a process called crossing-over
Results in the exchange of alleles between homologous chromosomes and produces new combinations of alleles
Alleles = alternative forms of the same gene (ex: blue eyes vs. brown eyes)
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Two cells produced by meiosis I now enter a second meiotic division
NO DNA replication before Meiosis II
Prophase II, Metaphase II, Anaphase II, Telophase II
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Paired chromatids separate
Produces: haploid cells (N)Haploid cells are DIFFERENTfrom each other
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