题目内容

琼脂糖凝胶电泳分离核酸时,在上样缓冲液中加指示剂的作用有( )

A. 增加上样比重
B. 提供颜色反应,便于操作
C. 指示电泳迁移过程
D. 直接指示核酸的泳动位置
E. 在紫外线的激发下可发出荧光三、填空题(8题)

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按贷款的风险程度,可将商业贷款分为 ( )

A. 正常贷款
B. 逾期贷款
C. 呆滞贷款
D. 呆账贷款

请查阅相关文献，阐述我校代表河北省参加历年少数民族传统体育运动会的战绩？

请阐述脚内侧起球这一技术的教学过程？

U5-1Directions: In this section, you'll hear some long conversations. At the end of each conversation, some questions will be asked. Both the conversation and the questions will be spoken only once. After each question, choose the best answer from the four choices marked A, B, C, and D.Questions 1 to 4 are based on the conversation you have just heard.1.A. Going to pubs to have a drink.B. Going to discos or rock concerts.C. Dining out.D. Going to see a film.2.A. Watching TV and listening to radio.B. Meeting friends in clubs.C. Watching live performances in theatres.D. Going to bars or clubs.3.A. Because theatres are far away from where they live.B. Because many people don’t like the performances.C. Because many people can’t understand live performances.D. Because the tickets are expensive.4.A. The superiority of entertainment in America to that of British.B. Why people have different ways of entertainment.C. Ways of entertainment in Britain and America.D. Changes of entertainment in America.Questions 5 to 8 are based on the conversation you have just heard.5.A. Doctor and patient.B. Secretary and boss.C. Teacher and student.D. Salesperson and customer6.A. Give a call to an advertising agency.B. Have a meeting with the staff.C. Meet one of the clients.D. Confirm the drawings of the toy.7.A. She thinks he is diligent.B. She thinks he is efficient.C. She thinks he is bossy.D. She thinks he is talented.8.A. To enjoy a day off.B. To take some measures to increase work efficiency.C. To delay some work till later.D. To cancel one of the appointments.Questions 9 to 12 are based on the conversation you have just heard.9.A. Wrestling.B. Collecting stamps.C. Collecting matches.D. Playing chess.10.A. In a restaurant.B. In a hotel.C. At a stadium.D. At home.11.A. Because they did not like it anymore.B. Because they ran out of money.C. Because they had little time for it.D. Because they thought it very boring.12.A. Changeable.B. Persistent.C. Indifferent.D. Naughty.