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Meiosis. Making Gametes (Egg & Sperm). Chromosome Structure. Centromere Position Varies. Interphase I. Each individual chromatid replicates. Prophase I. Crossing Over occurs. Each chromosome actively seeks out its homologous chromosome ( A.K.A. Homolog)
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Meiosis Making Gametes (Egg & Sperm)
Interphase I Each individual chromatid replicates
Prophase I Crossing Over occurs Each chromosome actively seeks out its homologous chromosome ( A.K.A. Homolog) After the homologous chromosomes pair, the structure is referred to as a tetrad (four chromatids). SYNAPSIS is the process of forming a tetrad
Metaphase I Centrosome Chromosomes are lined by the spindle fibers at the metaphase plate
Anaphase I Tetrad pulled apart separating each homologous chromosome.
Telophase I Two nuclear envelopes begin to surround the separate chromosomes and cytokinesis occurs
Prophase Ii Each dyad (1/2 a tetrad) is composed of a pair of sister chromatids
Metaphase Ii ? Similar to Metaphase I in that the dyads are lined up at a metaphase plate by the spindle fibers.
Anaphase Ii Separates the dyads into individual chromatids. Each sister chromatid ends up on one side of the cell.
Telophase Ii The chromosomal content of a haploid cell in one-half the chromosomal contentof a diploid cell ( n as opposed to 2n ) The nuclear envelopes forms around each set of DNA and the cytoplasm divides once again. 4 haploid cells have formed from one diploid cell.