SCIENCE
BOTANY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Leptotene
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Zygotene
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Diplotene
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Pachytene
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Detailed explanation-1: -Explanation: During pachytene, the third stage of prophase, the bivalent chromosomes form a tetrad and then cross over. The crossing over takes place between two non-sister chromatids. Zygotene is the second stage of prophase where the chromosomes pair with each other.
Detailed explanation-2: -Crossing over occurs during pachytene stage between non sister chromatids of a pair of homologous chromosomes. Diplotene is characterised by appearance of chiasma marking the locations at which crossing over has already occurred in the pachytene stage.
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: -Crossing over is the exchange of genetic materials between non-sister chromatids of homologous chromosome. It takes place at pachytene stage of prophase-I.
Detailed explanation-5: -So, the correct answer is ‘Pachytene’.