检测蛋白质时,事先留出一些黄豆组织样液,主要目的是( )
A:重复两次,结果准确
B:与加入双缩脲试剂后发生的颜色反应作对照
C:再用于还原糖的鉴定
D:失败后还可重做
X
Y
Z
W
阅读对话,判断正误。
A: Can I help you?
B: Yes. This red chess is nice. Can l try it on?
A: Of course. Here you are. Is it OK?
B: No, It’s too big.
A: How about the yellow one?
B: OK. Let me try. It’s just right. I’ll take it.
火灾发生时要做到“三救”,千万不能做到“三不”。( )