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 I
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metaphase I
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prophase II
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telophase II
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Detailed explanation-1: -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-2: -Crossing over (recombination) only occurs during Prophase 1 of Meiosis because at this point homologous chromosomes line up at the centre of the cell. Thus, the aligned chromosomes are able to have their legs intertwine with that of the chromosome beside them, in order for crossing over to occur.
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: -Explanation: During prophase I, homologous chromosomes pair with each other and exchange genetic material in a process called chromosomal crossover. The exchange occurs in segments over a small region of homology (similarity in sequence, ie., the same alleles).