CELL STRUCTURES AND FUNCTION
CELL DIVISION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Prophase of Mitosis
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Metaphase I of Meiosis
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Prophase II of Meiosis
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Prophase I of Meiosis
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Metaphase of Mitosis
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Detailed explanation-1: -Crossing over is an enzyme-mediated process, where the exchange of genetic material between non-sister chromatids of homologous chromosomes takes place. It occurs at the pachytene stage of prophase I of meiosis.
Detailed explanation-2: -Crossing over occurs only during prophase I. The complex that temporarily forms between homologous chromosomes is only present in prophase I, making this the only opportunity the cell has to move DNA segments between the homologous pair.
Detailed explanation-3: -Crossing over occurs during the pachytene stage of prophase in meiosis, however the chiasma are visible during. No worries!
Detailed explanation-4: -When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur. Crossing-over is the exchange of genetic material between homologous chromosomes. It results in new combinations of genes on each chromosome.
Detailed explanation-5: -How homologous chromosomes exchange fragments in prophase I.