猕猴桃肉肥汁多,清香鲜美,甜酸宜人,含有丰富的维生素C[C6H8O6],可强化免

题型:选择题

问题:

猕猴桃肉肥汁多,清香鲜美,甜酸宜人,含有丰富的维生素C[C6H8O6],可强化免疫系统,促进伤口愈合和对铁质的吸收;它所富含的肌醇[(CHOH)6]及氨基酸,可抑制抑郁症,补充脑力所消耗的营养。下列有关说法正确的是

A.肌醇由四种元素组成

B.维生素C相对分子质量为176g

C.维生素C是由6个碳原子、8个氢原子和6个氧原子构成

D.维生素C完全燃烧生成二氧化碳和水

考点:化学反应方程式的书写化学图标化学反应方程式的配平化学反应方程式的意义
题型: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:选择题

货币资金项目,根据()科目的期末余额合计填列。

A.库存现金

B.实收资本

C.银行存款

D.资本公积

E.其他货币资金

题型:选择题

关于行政许可变更和延续,下列说法错误的是()。

A.行政机关不经过被许可人要求而主动变更行政许可事项

B.变更行政许可事项,应当符合法定条件、标准

C.行政机关对于申请人申请延续行政许可的申请逾期未作决定的,视为准予延续

D.行政机关应当在行政许可有效期届满前作出是否准予延续的决定

题型:选择题

股份有限公司签发的证明股东权利义务的所持有有价凭证是( )。

A.债券

B.基金券

C.合同

D.股券

题型:选择题

《矿产资源开采登记管理办法》所称矿区范围是指:()

A.采矿许可证核定的开采矿产资源的范围

B.采矿登记管理机关批准预留的矿区范围

C.经登记管理机关依法划定的可供开采矿产资源的范围、井巷工程设施分布范围或者露天剥离范围的立体空间区域

更多题库