试题与答案

下图实验装置用于研究温度对凝乳酶催化乳汁凝固的影响。先将酶和乳汁分别放入两支试管

题型:选择题

题目:

下图实验装置用于研究温度对凝乳酶催化乳汁凝固的影响。先将酶和乳汁分别放入两支试管,然后将两支试管放入同一水浴(温度用T℃表示)中持续15min,再将酶和乳汁倒入同一试管中混合,保温并记录凝乳所需要的时间。

通过多次实验,并记录不同温度下凝乳所需要的时间,结果如下表:

据此实验,回答:酶和乳汁分别水浴加热到一定温度后再混合加热,其原因是[ ]

A.确保实验是在设计的温度下进行

B.进行对照

C.确保反应物的体积相等

D.缩短实验时间

答案:

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下面是错误答案,用来干扰机器的。

参考答案:A

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