满分5 > 高中英语试题 >

How Plants Branch Out to Access Water Ne...

How Plants Branch Out to Access Water

New research has discovered how plant roots sense the availability of water in soil and then adapt (适应)their shape to acquire water. The discovery could enable crops to be raised which are more adaptive to changes in climate conditions, such as the absence of water, and help ensure food safety in the future.

These findings, published in the journal Science, describe a new mechanism(机制) discovered by cooperating teams at the universities of Nottingham and Durham.

Roots are very important for plants to acquire water and nutrients(营养)from the soil. Water is necessary to plant growth , yet changing climatic conditions makes acquiring water from soil even more challenging. Plants are able to adapt to different soil moisture(湿润)conditions by changing their roots.

The researchers discovered that plant roots lacking a branching master gene were no longer able to branch out. They found that when roots have access to moisture, the certain gene remains active and promotes root branching, but when put in air, the gene is in activated, preventing root branching. The research has identified the certain protein which can inactivate root branching.

Professor Sadanandom explained: "This is hugely exciting as it opens up the possibility for us to help develop plants that could continue to branch roots even in challenging conditions such as the absence of water.''

Professor Bennett concluded: "Water is the key to plant growth, development and their survival. By studying how plant roots change their branching in response(回应)to water availability, we have uncovered a new mechanism. This opens the way to develop new crops better adapted to climate change and to help deliver global food safety."

It is absolutely imperative to ensure food safety worldwide. Crop production must double by 2050 to keep pace with global population growth. This target is even more challenging considering the effect of climate change on water availability. In this case, developing crops with better ability to acquire water would provide a solution.

1.The findings of the research may have a positive effect on several global issues EXCEPT

A.ensuring food safety B.preserving the agriculture

C.solving the absence of water D.increasing crop production

2.With the help of the findings, plants may be able to ________.

A.take in more nutrients B.change inactivated roots

C.grow in challenging conditions D.branch out without a special gene.

3.Which of the following best explains “imperative" in the last paragraph?

A.effective. B.hopeful.

C.impractical. D.urgent.

4.What is the new mechanism mentioned by Professor Bennett?

A.How a branching master gene responds to a particular nutrient.

B.How plant roots change their shape according to the soil moisture.

C.Why plants have different abilities to adapt to soil moisture conditions.

D.How the certain protein in activates root branching when accessible to water.

 

1.B 2.C 3.D 4.B 【解析】 本文是说明文。一项新的研究发现了植物根系是如何感知土壤中水分的可利用性,然后调整自身形状来获取水分的,并介绍了这一发现的意义。 1.细节理解题。根据第一段The discovery could enable crops to be raised which are more adaptive to changes in climate conditions, such as the absence of water, and help ensure food safety in the future.可知这一发现能使农作物更能适应气候条件的变化,增加产量,解决水资源缺乏,并有助于确保未来的食品安全。B项保护农业没有涉及,故选B。 2.细节理解题。根据第五段This is hugely exciting as it opens up the possibility for us to help develop plants that could continue to branch roots even in challenging conditions such as the absence of water.可知这个发现为我们提供了一种可能性,能够帮助我们培育出即使在缺水这样具有挑战性的条件下也能继续生根的植物。故选C。 3.猜测词义题。上段最后一句This opens the way to develop new crops better adapted to climate change and to help deliver global food safety.提到新发现为开发更好地适应气候变化的新作物和帮助实现全球食品安全开辟了道路。本句提到了ensure food safety worldwide(确保全球食品安全),根据上下文语境和常识可知此处指确保全球食物安全是绝对紧迫的,imperative与urgent同义,故选D。 4.推理判断题。根据第三段Plants are able to adapt to different soil moisture(湿润)conditions by changing their roots.(植物能够通过改变它们的根来适应不同的土壤湿润条件)和倒数第二段Professor Bennett说的By studying how plant roots change their branching in response(回应)to water availability, we have uncovered a new mechanism.(通过研究植物根系如何改变他们的分支来回应水的可用性,我们发现了一个新的机制。)由此判断出,这个新机制就是植物根系是如何根据土壤湿度改变形状的,故选B。
复制答案
考点分析:
相关试题推荐

    The origin of coffee? I never really thought about it. When I was a kid, coffee was always around. My parents drank coffee, my grandparents drank coffee, and all the adults I knew drank coffee. I thought I would drink it too when I was older, and of course. I did.

But there must have been a time before coffee. I don't remember coffee making an appearance in any of the Bible(圣经)stories I learned. Jesus changed water into wine, not coffee. Maybe if coffee had been around, he would have changed some of the water into coffee. Maybe that's what “B. C." in those timelines meant: "before coffee."

According to popular legend, the origin of coffee can be traced to a thousand years ago, when an Abyssinian(Ethiopian)goatherd(牧羊人)named Kaidi observed his goats dancing and jumping. When Kaidi investigated, he saw that the goats were happily eating the red berries(浆果)of an unfamiliar tree. Kaidi decided to try some, and when he did he joined the dancing goats and became “the happiest herder in happy Arabia''.

Some time later, a passing monk(和尚)observed Kaidi and the goats. When Kaidi told him about the berries, the monk thought they might be the answer to his prayers(祈祷). It seems that the monk was always falling asleep in the middle of prayers. When he ate the berries, he stayed awake. The unnamed monk came up with the idea of drying and boiling the berries. It came into the world. His fellow monks loved the new drink because it encouraged them to pray and it tasted good too.

So now that I know about Kaidi and his goats, if someday-in the far, far future, of course someone calls me an "old goat", I'll just smile, take another sip of coffee, and maybe do a little dance.

1.Why didn't Jesus change water into coffee?

A.Because Jesus didn't like coffee.

B.Because coffee didn't appear at that time.

C.Because it was not the right time to have coffee.

D.Because Jesus was better at changing water into wine.

2.What is the tone of the author when writing the text?

A.Serious. B.Objective.

C.Scientific. D.Humorous.

3.The underlined word “it" in paragraph 4 refers to ________.

A.a kind of new drink

B.a kind of food made by monks

C.a kind of soup needed to be boiled

D.a kind of drug encouraging people to keep awake

4.What is the best title for the text?

A.The Origin of Coffee.

B.The Development of Coffee.

C.The Popularity of Coffee in the World.

D.The Coffee-drinking Tradition in My Family.

 

查看答案

Marvel at These Freaks of Nature

The world is filled with unique, breathtaking sites-from boiling craters to caves full of lightning bugs. While a global disease or natural disasters shock our soul, we might not appreciate nature. In fact, enjoying the wonder of nature can provide some breaks from too much time indoors. These sites are great for you when looking for hope in some of Mother Nature's greatest offerings.

01 Fly Geyser Washoe County, Nevada

This geyser in northern Nevada, found surrounded by fields of grass was created by accident when a geothermal power company drilled a test well(井)where the geyser now sits in 1964. The combination of calcium carbonate deposits (碳酸钙沉淀物)and extremely hot water resulted in three nearly 6-foot-high, brightly colored red an« green hills that shoot hot water into the air.

02 The Marble Caves Aysen,  Chile

These caves --accessible only by boat - sit in the heart of Patagonia and wen formed over 6.000 years as water continued to splash against the solid rock formations to create these unique blue marble formations.

03 Lake Sorvagsvatn Vagar, The Faroe Islands

This freshwater lake is famous for its appearance of " floating above the ocean. Though it's actually not even 100 feet above sea level, from various camera angles, the lake looks like it is hundreds of feet above the ocean because of its juxtaposition(并列) with a dramatic waterfall and the cliff to its side.

04 Krka National Park Sibenik-knin, Croatia

This national park in southern Croatia is famous for having not one, but seven, gorgeous waterfalls streaming with greenish-blue waters, including the attractive Skradinskibuk waterfall. The clear water in its basin is often filled with visitors taking a dip.

1.According to the text, the following are all false except that ________.

A.these sites all have something to do with waterfalls

B.you may see lightning bugs in the Marble Caves by boat

C.Lake Sorvagsvatn are floating hundreds of feet above the ocean

D.the Flyer Geyser has 6 colorful hills shooting hot water into air

2.If visitors want to have a swim, they should go to ________.

A.the Flyer Geyser B.Lake Sorvagsvatn

C.Krka National Park D.the Marble Caves

3.What is the main purpose of the text?

A.To give basic facts about these freaks of nature.

B.To explain the reasons why these sites are great.

C.To call on people to appreciate these freaks of nature

D.To offer advice on how to visit these wonders of nature.

 

查看答案

假定你是李华,为迎接5月31日“世界无烟日”(World No Tobacco Day),你校学生会将办英语演讲比赛。请你根据以下要求写一则英文通知,内容包括:

1. 比赛的时间和地点;

2. 演讲内容(吸烟的害处,摆脱烟瘾的建议……)

3. 演讲时长报名方式及截止日期。

注意:1. 词数100左右;

2. 可以适当增加细节,以使行文连贯。

Notice

_________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

查看答案

假定英语课上老师要求同桌之间交换修改作文,你修改你同桌写的以下作文文中共有10处语言错误,每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。

增加:在缺同处加一个漏字符号(^),并在其下面写出该加的词。

删除:把多余的同用斜线(/)划掉。

修改:在错的词下划一横线,并在该词下面写出修改后的词。

注意:1. 每处错误及其修改均仅限一词;

2. 只允许修改10处,多者(从第11处起)不计分。

I had a wonderful summer holiday. Before the holiday, I have spent a lot of effort and time prepare for the College Entrance Examination. However, a good rest needed after the hard study of three years. I did many kinds of relaxed activities, such as going to the park, riding a likes, playing sports, etc. Besides, I took a boat trip along the Three Gorges Dam, that had been dreaming about for in a long time. And I read variety books about college life in our local library to get much knowledge. I also took part in some social activities active and found a part-time job so that I could learn more about society. What meaningful the holiday was!

 

查看答案

阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。

On Dec, 22, the couple---Charlotte Curtis is 105; John Henderson is 106---will celebrate their 80th wedding anniversary. The Guinness World Records have recognized the longevity of their love by naming the Hendersons the 1.(old) living married couple.

It all started in a zoology class in 1934. Students were 2.(seat) in the lecture tiered hall, and John Henderson, 21, sat 3.(direct) behind Charlotte Curtis. When he looked down, he liked the shy 20-year-old girl he saw in front of him. "I thought he was just a fine fellow, and I didn't mind his  4.(look) over my shoulder," Charlotte told The Washington Post in an interview. John and Charlotte 5.(marry) in a tiny ceremony---only two guests were present on Dec, 22, 1939. Charlotte took a teaching job; John first coached football and basketball and had a long career later at Humble Oil and Refining Co.

What's the couple's secret 6. their longevity? Living in moderation, they said. They eat right, don' t drink much, and John still 7.(exercise) at the community gym almost every day. Except for some hearing 8.(lose), both are in excellent health.

So, after 80 years, do they still argue, 9. have they figured it all out? No, they don't argue. But if you're looking forward to your marriage becoming more peaceful in your late golden years, take note: They never argued that much in the first place, and have always made a point 10.(settle) things before bedtime.

 

查看答案
试题属性

Copyright @ 2008-2019 满分5 学习网 ManFen5.COM. All Rights Reserved.