题干

下列有关叙述正确的是(  )

A:只有细胞内的核酸才是携带遗传信息的物质

B:沸水浴加热之后,胰岛素仍可以与双缩脲试剂产生紫色反应

C:多糖在细胞中不与其他分子相结合

D:用甲基绿和吡罗红混合染色SARS病毒可观察到DNA和RNA的分布

上一题 下一题 0.0难度 选择题 更新时间:2020-01-11 07:34:22

答案(点此获取答案解析)

B

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Fill in the blanks with proper words(在短文的空格内填入适当的词,使其内容通顺。每空格限填一词,首字母已给)

explains      common    used    change      besides     usually 

    ZhangMing, a college graduate from Shandong, created a 9-page"Wechatguide". With drawings and simple words, the step-by-step guide e____ how to send messages, take pictures and make video calls. Zhang made the guide for his parents. "My parents are getting old. They need an easy way to learn how to use technology, "he said.

    Zhang's experience is c____ nowadays.Worldwide,40percent of parents learn about new technologies, including computers, mobile Internet and social media, from their children, according to a study from the International Communication Association in 2017.

    Parents u ____ to teach their kids about almost everything. Now for the first time, the teachers become the students, and the students turn into the teachers.

    The c____ of the roles comes from the rapid development of society and technology says Zhou Xiaohong, a sociology professor from Nanjing University. Zhou said the Internet and other forms of media give children ways to get information b____  from asking older generations. Therefore, in the age of information, it's possible that children know more than their parents do.

    According to the China Internet Network Information Center, 56.7 percent of Internet users and 67.2 percent of social media users in China are under the age of 30. The younger generation u____ acts as a link between their family and the new environment. But when they teach their parents new technologies, parents can connect to the new world by themselves, noted Zhou.

    In Zhang Ming's eyes, teaching his parents about Wechat brings him c____ to his parents."People can communicate more by using new technology. Why should we keep our parents out? "said Zhang.