题干

下面是某兴趣小组探究教室里是否有细菌和真菌的实验方案,请你帮助设计完成

材料用具:1号和2号装有牛肉汁培养基的培养皿(已高温灭菌)、透明胶带、放大镜.

一,提出问题:教室里的空气中是否有多种细菌和真菌?

二,作出假设:教室的空气里有细菌和真菌.

三,制订计划并实施:

①1号培养皿的处理方法:打开培养皿,暴露在教室的空气中5﹣10分钟,再盖上,封好;2号培养皿不做处理,在实验中起____作用.

②把两个培养皿放在____的地方.

四,观察结果,得出结论:

①1号培养皿的现象:____

②2号培养皿的现象:无菌落形成.

③你的结论是____

通过以上实验可知,细菌和真菌适合于生活在____的环境中.

上一题 下一题 0.0难度 选择题 更新时间:2018-10-07 04:43:53

答案(点此获取答案解析)

\u5bf9\u7167,\u76f8\u540c\u9002\u5b9c\u6761\u4ef6\u4e0b\u57f9\u517b,\u6709\u591a\u79cd\u83cc\u843d\u5f62\u6210,\u6559\u5ba4\u7684\u7a7a\u6c14\u91cc\u6709\u591a\u79cd\u7ec6\u83cc\u548c\u771f\u83cc,\u8425\u517b\u4e30\u5bcc\u3001\u6e29\u5ea6\u9002\

同类题1

阅读理解

    Science has a lot of uses. It can uncover laws of nature, cure diseases, make bombs, and help bridges to stand up. Indeed science is so good at what it does that there's always a temptation(诱惑) to drag it into problems where it may not be helpful. David Brooks, author of The Social Animal: The Hidden Sources of Love, Character, and Achievement, appears to be the latest in a long line of writers who have failed to resist the temptation.

    Brooks gained fame for several books. His latest book The Social Animal, however, is more ambitious and serious than his earlier books. It is an attempt to deal with a set of weighty topics. The book focuses on big questions: What has science revealed about human nature? What are the sources of character? And why are some people happy and successful while others aren't?

    To answer these questions, Brooks surveys a wide range of disciplines(学科).Considering this, you might expect the book to be a dry recitation of facts. But Brooks has structured his book in an unorthodox(非常规的), and perhaps unfortunate, way. Instead of introducing scientific theories, he tells a story, within which he tries to make his points, perhaps in order to keep the reader's attention. So as Harold and Erica, the hero and heroine in his story, live through childhood, we hear about the science of child development and as they begin to date we hear about the theory of sexual attraction. Brooks carries this through to the death of one of his characters.

    On the whole, Brooks's story is acceptable if uninspired. As one would expect, his writing is mostly clear and, to be fair, some chapters stand out above the rest. I enjoyed, for instance, the chapter in which Harold discovers how to think on his own. While Harold and Erica are certainly not strong or memorable characters, the more serious problems with The Social Animal lie elsewhere. These problems partly involve Brooks's attempt to translate his tale into science.