Metaphase I and Independent Orientation
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In metaphase I, every tetrad aligns at the metaphase plate, and each tetrad's maternal-versus-paternal orientation is set independently of every other tetrad.
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A cell with two chromosome pairs can align them in either of two ways, and a cell with 23 pairs has millions of arrangements.
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Independent orientation shuffles whole homologs between poles, separate from the segment-level shuffling crossing over produces.