CELL STRUCTURES AND FUNCTION
CELL DIVISION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Pachytene
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Zygotene
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Diplotene
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Diakinesis
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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 during the pachytene stage of prophase in meiosis, however the chiasma are visible during. No worries!
Detailed explanation-3: -Crossing over takes place during the pachytene stage. During this stage, non-sister chromatids of homologous chromosomes may exchange segments over regions of homology.
Detailed explanation-4: -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-5: -Pachytene is the third stage of meiosis prophase-1 (a five-stage process). It is preceded by the zygotene stage, where synapsis, i.e. pairing of homologous chromosomes take place. Recombination or crossing over takes place at this stage.