()是人民群众安居乐业的家园,是党和国家许多政策措施落实的“最后一公里”,对于巩固党

题型:单项选择题

问题:

()是人民群众安居乐业的家园,是党和国家许多政策措施落实的“最后一公里”,对于巩固党的执政基础具有重大意义。

A.城市中心

B.城镇核心区

C.城乡社区

D.偏远地区

考点:事业单位招聘考试2017年6月时事政治2017年6月时事政治题库
题型:单项选择题

A new study finds that plants communicate with one another to warn of danger.

We often consider plants as the furniture of the natural world. They don’t move; they don’t make sounds, they don’t seem to act on anything. But as is often the case, plants talk to each other all the time. And the language is chemical.

Over the years, scientists have reported that different types of plants, from trees to tomatoes, give out chemicals into the air to help neighboring plants. These chemical warnings can spread information about one plant’s disease or infestation(虫害), so other plants can protect themselves. But how plants receive and act on many of the information exactly is still mysterious.

In this week’s Science Magazine, researchers in Japan offered some explanations. They have found out one chemical message and traced it all the way from beginning to end.

The scientists looked at tomato plants infested by a common pest(害虫). To start out, they grew plants in two separate plastic spaces connected by a tube(管子). One plant was infested and placed upwind and the other was uninfested and placed downwind. The downwind plants were later exposed(暴露) to the pest. The results showed that plants near sick neighbors before were able to protect themselves better against the pest.

They found one chemical appeared more often in the exposed plants. The chemical is called HexVic. The scientists discovered where HexVic come from, and put it over healthy plants. Those plants were then able to produce HexVic. Researchers made sure that uninfested plants could fight off bugs and diseases. How do they know when to protect themselves? They are warned first by their friendly plant neighbors.

It is not a simple story, and it may be happening in more plant species than tomatoes. It may also be happening with more chemical signals that are still unknown to us. In a word, we know that plants not only communicate, but also look out for one another.

小题1:The underlined “traced” in the fourth paragraph probably means _________ here.

A.reported

B.followed

C.doubted

D.developed小题2:For scientists, which are the right steps to watch tomato plants infested by a pest?

①  Place the infested plant upwind.

②  Place the uninfested plant downwind.

③  Expose the downwind plants to the pest.

④  Grow plants in two separate plastic spaces connected by a tube.

A.③①②④

B.①④③②

C.④①②③

D.④②①③小题3:You can put the sentence “The researches also studied leaves from exposed plants and unexposed plants.” At the beginning of

A.Paragraph 3

B.Paragraph 4

C.Paragraph 5

D.Paragraph 6小题4:Which of the following can be the best title of this passage?

A.Communicating Plants and Terrible Diseases

B.Talking Plants and Friendly Warnings

C.Protecting Plants and Clear Information

D.Growing Plants and Mysterious Chemicals

题型:单项选择题

设{an}和{bn}均为无穷数列.

(1)若{an}和{bn}均为等比数列,试研究:{an+bn}和{anbn}是否是等比数列?请证明你的结论;若是等比数列,请写出其前n项和公式.

(2)请类比(1),针对等差数列提出相应的真命题(不必证明),并写出相应的等差数列的前n项和公式(用首项与公差表示).

题型:单项选择题

读“我国某地区农业用地分布图”,回答下列问题:(10分)

(1)据图分析A所在省的地形、地势特点。

(2)请分析说明A—B—C年降水量空间分布的大致特点,并分析原因。

题型:单项选择题

物流成本的()特性要求从物流系统高度寻求总体的最优。

A.隐含性

B.物流效益背反

C.成本削减的乘数效应

D.非可控现象

题型:单项选择题

足癣感染病人,患侧小腿红肿伴有畏寒、发热。体格检查发现患侧小腿皮肤为片状红疹,中间淡、边缘清并稍隆起,腹股沟淋巴结肿大。所患疾病是()。

A.急性淋巴管炎和淋巴结炎

B.急性网状淋巴管炎

C.急性蜂窝织炎

D.急性淋巴结炎

E.痛风

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