Do Your Experiments Require Total RNA or mRNA? One of the first decisions that the researcher has to make when detecting or quantitating RNA is whether to isolate total RNA or poly(A)-selected RNA (also commonly referred to as mRNA). This choice is further complicated by the bewildering array of RNA isolation kits available in the marketplace. In addition the downstream application influences this choice. The following

The primary purpose of a buffer is to control the pH of the solu￾tion. Buffers can also play secondary roles in a system, such as controlling ionic strength or solvating species, perhaps even affect￾ing protein or nucleic acid structure or activity. Buffers are used to stabilize nucleic acids, nucleic acid–protein complexes, proteins

If You Don’t Define the Project, the Project Will Define You One of the first and toughest questions researchers must answer to foster success in the lab is: What do I have to accom￾plish? This requires you to understand your purpose to the

《英语写作基础》是全国高等教育自学考试英语专业基础阶段（专科阶段）的一门重要的实践课程，本科程着重培养应考生英语写作的基本技能，重点教授英语写作的最基础内容。主要包括三大部分：句子的组成，段落的写作，概要及应用文写作

本文研究一位外籍教师如何使用思辨能力方法给中国学生上英语辩论课,通过参与和观察课堂,访谈教师和学生对该教学进行定性分析,对语言教学中如何把技能训练和思维训练很好地结合起来,提出了一些建议

一、词汇和语法（本大题共 20 小题，每小题 1 分，共 20 分） 根据句子的意思选择一个正确的答案，错选、多选或未选均无分。 1. It‘s______ by coach from Melbourne to Sydney. A. a nine hour‘s journey B. a nine hour journey C. a nine hours‘ journey D. a nine-hours journey

一、词汇和语法（本大题共 20 小题，每小题 1 分，共 20 分） 根据句子的意思选择一个正确的答案，错选、多选或未选均无分。 1. The furniture in her room is quite different from ____________ in the exhibition hall. A. that B. that one C. these D. those ones

一、 词汇和语法（本大题共 20 小题，每小题 1 分，共 20 分） 根据句子的意思选择一个正确的答案，错选、多选或未选均无分。 1. The time has come for the company to __________ after years of rapid expansion. A. consist B. consider C. consolidate D. combine

第一部分 选择题（共 50 分） (一) 词汇和语法(本大题共 20 小题，每小题 1 分，共 20 分) 根据句子的意思选择一个正确的答案。答案标在答题纸上。 1.Flight nineteen from New York and Washington is now arriving at _____. A. the two gate B. gate two C. the gate two D. second gate

一、词汇和语法（本大题共 20 小题，每小题 1 分，共 20 分） 根据句子的意思选择一个正确的答案。答案标在答题纸上。 1．I keep my reference books near my desk for _______. A．convention B．convenience C．conference D．confidence