题目内容

【题目】请回答下列问题:

1细胞膜主要由 组成,还有少量

2功能越复杂的细胞膜,蛋白质的 越多。

3植物传粉后,同种和不同种花粉都会落在雌蕊柱头上,同种花粉粒能萌发,不同种花粉粒一般不能萌发,这与细胞间相互识别有关,细胞识别体现了细胞膜的 功能。

4植物细胞在细胞膜外面还有一层 ,它的主要化学成分是 ,对植物细胞有 作用。

【答案】

1脂质和蛋白质 糖类

2种类和数量

3信息交流

4细胞壁 纤维素和果胶 支持和保护

【解析】

1细胞膜主要由脂质和蛋白质组成,还有少量糖类。

2功能越复杂的细胞膜,蛋白质的种类和数量越多。

3植物传粉后,同种和不同种花粉都会落在雌蕊柱头上,同种花粉粒能萌发,不同种花粉粒一般不能萌发,这与细胞间的相互识别有关,细胞识别体现了细胞膜进行细胞间的信息交流的功能。

4植物细胞在细胞膜外面还有一层细胞壁,它的主要化学成分是纤维素和果胶,对植物细胞有支持和保护作用。

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【题目】D

An international study of more than 13, 000 adults found that many people say modern technology has affected relations with their partners. Almost 40 percent of those questioned said their partners paid more attention to their mobile devices than to them.

The research included both old and new relationships. Thirty-three percent of those asked reported that they had to compete against a mobile device for attention on a first date.

Apparently, we have as much love for our digital devices as for the people we love. The survey found that adults spend almost equal amounts of time online at home as they do interacting directly. And a lot of married couples, friends and family members argue about time spent on mobile devices.

Rules or time limits on a device might be good, in theory. However, the survey found that 45 percent of those questioned do not set rules. Another 45 percent said they got into arguments about how much they are on their phones when spending time with loved ones. The lack of social rules about digital behavior might be the result of the newness of the issue.

Past generations did not have the technologies. In this situation, our elders know nothing. In fact, the knowledge and ability is moving towards the youngest generation thats using the technology because theyre the ones bounding forward fearlessly, and finding out what ways they can get in trouble.

That trouble may include the sharing of sensitive information. The research found nearly 30 percent of couples share passwords to social media sites. This could be a problem when relationships end.

The study advises that people step away from electronic devices to truly connect with other people. Understand the value of distancing yourself from your device and allow yourself to be engaged with that person that means the most to you.

【1】What did the study find about modern technology?

A. People depend too much on it.

B. It breaks relations between partners.

C. Partners need it to develop relations.

D. It has a bad effect on human relations.

【2】Whats the problem with the digital device?

A. It takes up too much time.

B. It is dangerous to play.

C. It causes tiredness in married couples.

D. It takes away all love from loved ones.

【3】 What can be inferred from Paragraph 4?

A. People disagree with limiting mobile use.

B. Rules need to be made to limit mobile use.

C. The majority of users set rules to use a device.

D. More and more people will use phones wisely.

【4】What can be the best title for the text?

A. We Cant Live Without a Cell Phone.

B. For Love, Put Aside the Phone!

C. How Powerful Electronic Devices Are!

D. Your Time Will Be Killed by the Phone.

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近况及为全运会做准备

(2017·天津假设你是李津,与你以前的外籍教师Mrs. Green 一直保持联系。近日她来信询问你的近况,请根据以下提示给她回复一封邮件。

(1)简要介绍自己的学习和生活;

(2)告知你已成为八月底在津举办的第十三届全运会的志愿者,并介绍为此所做的准备(如深入了解天津等);

(3)希望她有机会重访天津。

注意:

(1)词数不少于100;

(2)可适当加入细节,使内容充实、行文连贯;

(3)开头已给出,不计入总词数。

参考词汇:第十三届全运会 the 13th National Games

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