CELL DIVISION
THE CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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chromosomes lining up
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crossing over of chromosomes
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separation of chromosomes
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chromosomes pulling apart
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Detailed explanation-1: -During meiosis, homologous chromosomes (1 from each parent) pair along their lengths. The chromosomes cross over at points called chiasma. At each chiasma, the chromosomes break and rejoin, trading some of their genes. This recombination results in genetic variation.
Detailed explanation-2: -Crossing over is important for the normal segregation of chromosomes during meiosis. Crossing over also accounts for genetic variation, because due to the swapping of genetic material during crossing over, the chromatids held together by the centromere are no longer identical.
Detailed explanation-3: -Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism’s offspring).