下列有关科学研究、实验方法和实验原理的叙述,正确的是A.观察

下列有关科学研究、实验方法和实验原理的叙述,正确的是

A.观察根尖分生组织细胞的有丝分裂时,解离液的作用是为了让细胞分散开来

B研究红绿色盲的遗传方式应该在患者家系中调查

C纸层析法分离叶绿体色素的实验结果表明,叶绿素b在提取液中溶解度最低

D探究温度对酶活性的影响时,可选用过氧化氢作为反应物

答案

相关题目

某厂1月份产量为a吨,以后每个月比上一个月增产x%,则该厂3
某厂1月份产量为a吨,以后每个月比上一个月增产x%,则该厂3月份的产量(单位:吨)为(  )A.a(1+x)2       B.a(1+x%)2      C.a+a·x%       D.a+a
       If you had lived in the Middle Ages,you ________the chance to a
       If you had lived in the Middle Ages,you ________the chance to appreciate the art works of Leonardo da Vinci. A.won’t have had       B.wouldn’t have  C.wouldn’t have
Henry escaped ____ by admitting his mistake. A. being punished B. having been p
Henry escaped ____ by admitting his mistake. A. being punished B. having been punished C. having punishedD. punishing  
所谓合金,就是不同种金属(也包括一些非金属)在熔化状态下
所谓合金,就是不同种金属(也包括一些非金属)在熔化状态下形成的一种熔合物,根据下列四种金属的熔沸点:NaCuAlFe 熔点97.5℃1 083℃660℃1 535℃ 沸点883℃2
By the time he leaves, he ______ many friends here.   A. has made   B. will h
By the time he leaves, he ______ many friends here.   A. has made   B. will have made  C. had made      D. will make  
Crime has its own cycles, a magazine reported some years ago. Police records th
Crime has its own cycles, a magazine reported some years ago. Police records that were studied for five years from over 2,400 cities and towns show a surprising link between changes in the season an
下列化肥不能与碱性物质混放或混用的是A.碳铵B.硝铵C.
下列化肥不能与碱性物质混放或混用的是A.碳铵B.硝铵C.硫铵D.硫酸钾
在人与自然的关系问题上,中国古代有过许多探索与思考。
在人与自然的关系问题上,中国古代有过许多探索与思考。据所学知识回答以下问题: (1)战国和两汉时期的思想家在自然现象与社会政治等方面的

最新题目