题干

在“探究培养液中酵母菌种群数量的动态变化”实验中,同等实验条件下分别在4支大试管中进行培养(见表),均获得了“S”型增长曲线.根据表中实验设置,判断下列说法错误的(  )

试管号

培养液体积(mL)

10

5

10

5

起始酵母菌数(103个)

10

5

5

10

A:试管Ⅳ内种群的K值与试管Ⅰ相同

B:4支试管内的种群达到K值所需时间不同

C:4支试管内的种群在变化初始阶段都经历了“J”型增长

D:试管Ⅱ内的种群数量先于试管Ⅲ开始下降

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A

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    Years ago, I lost my sight completely. I would do anything for a 1 . In fact, desperate and 2 , I tried every supplement, experimental trial, diet and anything anyone 3 . All for nothing.

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    “We're so 10 with the results,” the receptionist said the next day, “that we want to send you on your first 11 tomorrow. It's in the Immigration and Naturalization Court.”

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