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【简答题】
某中学老师自制大蒜提取液,希望这种简便、经济的提取液能够高效的杀灭餐具上的细菌,老师完成了下面的探究实验: (1)制作提取液:老师将大蒜榨汁后制成提取液,具体做法如下表所示。请根据表中数据,在表中的括号内填出1#提取液应加入的冷开水量。 (2)使用方法:将餐具浸泡在提取液中10min后取出冲洗。 (3)样品抽取:将经过_______处理的滤纸贴在餐具表面lmin,然后再将滤纸放到50ml无菌水中,充分振荡后制成原液。再取1mL原液加入_________ml无菌水中摇匀制成10倍稀释液。 (4)分离及培养:用________法分离细菌。分别取1ml原液和10倍稀释液,分别加到-美蓝培养基中,用灭菌、消毒后的__________(用具),将原液和稀释液均匀涂布到整个平板上。每个浓度各做三个培养皿,其目的是____________。本实验另设1m1无菌水涂布在未接种的培养皿为空白对照,原因是排除 ___________ 。最后在37℃培养48h。 (5)观察记录:在空白处,设计1#提取液实验组的观察记录表 (6)结果分析:统计数据,得到消毒前后的菌落总数变化(单位cfu/cm 2 ,每平方厘米样品中含有的细菌菌落总数) 根据消毒前后的数据可知_______________________。 2#提取液效果高于1#,分析可能的原因____________。 请你给老师提出需要进一步研究的问题:____________________。
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举一反三
【单选题】Why does Dr. Downs want his students to get these five books?
A.
He is very strict.
B.
All his students are rich.
C.
These books are not expensive.
D.
He wants to discuss them in detail.
【单选题】( )指的是未知的优待开拓的市场空间,竞争虽不大但是充满买家需求的行业。
A.
绿海行业
B.
黄海行业
C.
红海行业
D.
蓝海行业
【单选题】When he saw all his books _____ here and there on the floor, he knew that something terrible _____. [     ]
A.
lying; must have happened
B.
lie; must happen
C.
lay; might have happened
D.
had lain; could have happen
【单选题】( )指的是未知的优待开拓的市场空间,竞争虽不大但是充满买家需求的行业。
A.
红海行业
B.
绿海行业
C.
黄海行业
D.
蓝海行业
【单选题】You read his books, and he wants to read your books ____. [     ]
A.
in all
B.
any more
C.
at all
D.
as well
【简答题】说明“产品报价单”的制作要求及作用 1 合并与拆分单元格 2 移动与复制数据 3 插入与删除单元格 4 清除与修改数据 5 查找与替换数据 6 调整单元格行高与列宽 7 套用表格格式 提交方式多样:可文字论述、截图、上传附件等
【单选题】All would resurface in his books, together with the colorful language that he soaked with a memory that seemed phonographic. ( Para. 4)
A.
All would reappear in his books, written in the colorful language that he seemed to be able to remember and record as accurately as phonograph.
B.
All would reappear in his books, written by Mark Twain by using a  phonograph.
【多选题】下列关于资本公积和留存收益区别的说法中正确的有( )
A.
资本公积主要来自资本溢价(股本溢价)
B.
留存收益主要来源于企业生产经营活动实现的利润
C.
资本公积来源于企业的实现的利润
D.
留存收益包括资本公积和未分配利润
【单选题】指的是未知的优待开拓的市场空间,竞争虽不大但是充满买家需求的行业。
A.
蓝海行业
B.
红海行业
C.
黄海行业
D.
绿海行业
【单选题】. What a pity! All his property, the books, the pictures and the house, __________consumed by the big fire.
A.
were
B.
was
C.
had been
D.
have been
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