Question

【題目】How Plants Branch Out to Access Water

New research has discovered how plant roots sense the availability of water in soil and then adapt (適應(yīng))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(機(jī)制) discovered by cooperating teams at the universities of Nottingham and Durham.

Roots are very important for plants to acquire water and nutrients(營(yíng)養(yǎng))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(濕潤(rùn))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(回應(yīng))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】

本文是說明文。一項(xiàng)新的研究發(fā)現(xiàn)了植物根系是如何感知土壤中水分的可利用性，然后調(diào)整自身形狀來獲取水分的，并介紹了這一發(fā)現(xiàn)的意義。

【1】細(xì)節(jié)理解題。根據(jù)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.可知這一發(fā)現(xiàn)能使農(nóng)作物更能適應(yīng)氣候條件的變化，增加產(chǎn)量，解決水資源缺乏，并有助于確保未來的食品安全。B項(xiàng)保護(hù)農(nóng)業(yè)沒有涉及，故選B。

【2】細(xì)節(jié)理解題。根據(jù)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.可知這個(gè)發(fā)現(xiàn)為我們提供了一種可能性，能夠幫助我們培育出即使在缺水這樣具有挑戰(zhàn)性的條件下也能繼續(xù)生根的植物。故選C。

【3】猜測(cè)詞義題。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.提到新發(fā)現(xiàn)為開發(fā)更好地適應(yīng)氣候變化的新作物和幫助實(shí)現(xiàn)全球食品安全開辟了道路。本句提到了ensure food safety worldwide（確保全球食品安全），根據(jù)上下文語境和常識(shí)可知此處指確保全球食物安全是絕對(duì)緊迫的，imperative與urgent同義，故選D。

【4】推理判斷題。根據(jù)第三段Plants are able to adapt to different soil moisture(濕潤(rùn))conditions by changing their roots.(植物能夠通過改變它們的根來適應(yīng)不同的土壤濕潤(rùn)條件)和倒數(shù)第二段Professor Bennett說的By studying how plant roots change their branching in response(回應(yīng))to water availability, we have uncovered a new mechanism.(通過研究植物根系如何改變他們的分支來回應(yīng)水的可用性，我們發(fā)現(xiàn)了一個(gè)新的機(jī)制。)由此判斷出，這個(gè)新機(jī)制就是植物根系是如何根據(jù)土壤濕度改變形狀的，故選B。