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同类题5

某些媒体报道“转基因植物油对人类的健康不利”,也有专家说“转基因植物油是安全的”,到底是否安全呢?某班初二学生针对这一问题进行了如下探究实验.

(一)实验器材:普通植物油,转基因植物油,稻谷若干,小白鼠若干,两个规格一样且空间足够大的铁笼等.

(二)该同学提出的问题:转基因植物油对人类的健康是否有影响.

(三)实验过程:

(1)将两个铁笼分别贴上甲组和乙组标签,选取两只身体健康状况良好、大小一致、性别相同的小白鼠,分别置于甲、乙铁笼中.

(2)称取一定重量的同种稻谷平均分成两份,分别拌适量且等量的普通植物油(A料)和转基因植物油(B料)待用.

(3)甲组饲喂适量A料,乙组饲喂____ B料.

(4)饲喂一段时间后,观察并记录甲、乙两组小白鼠的生长状况.

(5)预测实验结果和结论:

①若两组小白鼠的生长状况有明显差异,则说明转基因植物油对人类健康____ (填有或无)影响.

②若两组小白鼠的生长状况无明显差异,则说明转基因植物油对人类健康____ (填有或无)影响.

(四)请根据上述实验设计回答下列问题:

(1)请你为该同学做出假设,你的假设是:____ 

(2)该同学设置甲组的目的是对照,该实验的实验变量是____ 

(3)该实验选取小白鼠的数目过少,会增大实验的____ ,导致实验结论可信度不高.