题干

下图表示雄果蝇细胞分裂过程中DNA含量的变化。下列叙述中,正确的是 (  )

A:若图1表示减数分裂,则CD段表示同源染色体分开

B:若图1表示减数分裂,则BC段一个细胞中可能含有0个或1个Y染色体

C:若两图均表示有丝分裂,则两图的DE段一个细胞内染色体数目都加倍

D:两图的CD段都发生了着丝点分裂

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答案(点此获取答案解析)

B

同类题3

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____ Jane thinks a bicycle is __________ than a car if you live in a town.
____ It's convenient to use a bicycle because you can ride it to anywhere and needn't worry about __________.
____ When it is __________ in summer, Jane rides her bicycle.
____ For short journey, Jane’s husband doesn’t want to wait for a bus. He would like to __________.
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