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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prophase I of meiosis
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interphase
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during all stages of meiosis I
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Detailed explanation-1: -Crossing over takes place at the pachytene stage of prophase I of Meiosis. Crossing over includes the symmetrical division of chromatids, and the reciprocal exchange and crosswise assembly of segments between non-sister chromatids, often breaking linkage. This results in the recombination of genes.
Detailed explanation-2: -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-3: -Crossing over occurs during the pachytene stage of prophase in meiosis, however the chiasma are visible during. No worries!
Detailed explanation-4: -During prophase I, the pairs of homologous chromosomes come together to form a tetrad or bivalent, which contains four chromatids. Recombination can occur between any two chromatids within this tetrad structure.