下列有关实验过程的叙述中，正确的是（）_刷题宝

题干

下列有关实验过程的叙述中，正确的是（）

A：用猪肝探究H₂O₂酶的高效性：先进行研磨，后进行不同温度下水浴

B：用洋葱鳞片叶内表皮观察DNA和RNA的分布：先染色再水解

C：用梨鉴定可溶性还原糖的存在：斐林试剂甲液和乙液按2：1比例混合后再注入

D：用天竺葵探究光合作用是否产生淀粉：先黑暗处理，后光照

上一题下一题 0.0难度选择题更新时间:2018-12-15 06:26:03

答案(点此获取答案解析）

D

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There is____(一碗水) on the table．

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下列句子中加线成语运用不正确的一项是( )

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While shopping, people sometimes can’t help ____ into buying something they don’t really want.

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仔细阅读下列材料，根据阅读内容选择正确答案

It's not WASTE until it is WASTED!

With the World Environment Day coming, our school is now requiring every student to form a habit of sorting the waste. Here in our schoolyard we lay four different colors of rubbish bins for different kinds of rubbish. The red is for harmful waste; the blue is for waste that can be recycled(循环再用); the green is for kitchen waste; the yellow is for other waste.

    The followings are some instructions for you.
Glass: Empty bottles without caps can be recycled to make new glass bottles.
Warning: Mirrors and light bulbs must not be included in the glass waste.
Paper: Newspapers, magazines, boxes must be clean enough to be recycled.
Warning: Paper tissues and wallpaper are not recyclable as paper and should be kept separately.（分别地）
PMD waste: Packaging made of Plastic or Metal and Drink boxes are used to make new packaging.
Warning: Plastic pots (e.g. yoghurt pots), plastic bags must not be included with the PMD waste.
Harmful waste: out-of-date drugs, used batteries(电池), paint and oil …
    Besides, if you don't need your old bikes at all, our school volunteers will collect them. We're going to fix them up and then give them away to kids who don't have enough money for a bike.
    To find out more about recycling, you can visit our school website.

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