Question

【题目】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 safetyB.preserving the agriculture

C.solving the absence of waterD.increasing crop production

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

A.take in more nutrientsB.change inactivated roots

C.grow in challenging conditionsD.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.

Answer 1

【答案】

【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。