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Crossing-over occurs during which of the following phases in meiosis?

Crossing-over occurs during which of the following phases in meiosis? Correct Answer Prophase I

A Crossing-over (exchange of genetic material) occurs in prophase I of meiosis. Eliminate (B) because during metaphase I, the tetrads line up at the metaphase plate. Choice (C) is also incorrect; during anaphase, the tetrads separate. Finally, you can eliminate (D) because during prophase II, the chromosomes become visible again.

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