CELL DIVISION
MEIOSIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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extra chromosomes are found in the sex cell
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chromosomes of the sex cell are doubled
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chromosomes of the sex cell are halved
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meiosis never completes
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Detailed explanation-1: -Mitotic nondisjunction can occur due to the inactivation of either topoisomerase II, condensin, or separase. This will result in 2 aneuploid daughter cells, one with 47 chromosomes (2n+1) and the other with 45 chromosomes (2n-1). Nondisjunction in meiosis I occurs when the tetrads fail to separate during anaphase I.
Detailed explanation-2: -Likewise, abnormal separation can occur in meiosis when homologous pairs fail to separate during anaphase I. This also results in daughter cells with different numbers of chromosomes. The phenomenon of unequal separation in meiosis is called nondisjunction.
Detailed explanation-3: -But if meiosis doesn’t happen normally, a baby may have an extra chromosome (trisomy), or have a missing chromosome (monosomy). These problems can cause pregnancy loss. Or they can cause health problems in a child.