plants to 选择 Lightgetsthrough,andthisisessen-tial________plantstomakethefood[A]with[B]from[C]under[D]for
plants to 选择
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Once he raised his head ___________ the automobile hood to talk to me. A. /B. fromC. underD. from under
CPlants can’t communicate by moving or making sounds, as most animals do. Instead, plants produce volatile compounds, chemicals that easily change from a liquid to a gas. A flower’s sweet smell, for example, comes from volatile compounds that the plant produces to attract insects such as bugs and bees.Plants can also detect volatile compounds produced by other plants. A tree under attack by hungry insects, for instance, may give off volatile compounds that let other trees know about the attack, In response, the other trees may send off chemicals to keep the bugs away- or even chemicals that attract the bugs’ natural enemies.Now scientists have created a quick way to understand what plants are saying: a chemical sensor(传感器) called an electronic nose. The “e-nose” can tell compounds that crop plants make when they’re attacked. Scientists say the e-nose could help quickly detest whether plants are being eaten by insects. But today the only way to detect such insects is to visually inspect individual plants. This is a challenging task for managers of greenhouses, enclosed gardens that can house thousands of plants.The research team worked with an e-nose that recognizes volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds. Based on these interactions, the e-nose gives off electronic signals that the scientists analyze using computer software.To test the nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all common greenhouse crops. Then the scientists collected samples of air around damaged leaves from each type of crop. These plants had been damaged by insects, or by scientists who made holes in the leaves with a hole punch (打孔器).The e-nose, it turns out, could identify healthy cucumber, pepper and tomato plants based on the volatile compounds they produce. It could also identify tomato leaves that had been damaged. But even more impressive, the device could tell which type of damage – by insects or with a hole punch – had been done to the tomato leaves.With some fine tuning, a device like the e-nose could one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this could also be used to identify fruits that are perfectly ripe and ready to pick and eat, says Natalia Dudareve, a biochemist at Purdue University in West Lafayette, Ind. who studies smells of flowers and plants. Hopefully, scientists believe, the device could bring large benefits to greenhouse managers in the near future.49. We learn from the text that plants communicate with each other by______.A. making some sounds B. waving their leavesC. producing some chemicals D. sending out electronic signals
Under her leadership, the group’s ______ grew from less than one million dollars to more than ten million.A dataBbudgetCitemDpiece
He hides behind door or creeps under a table to () from his enemies. A.escapeB.escapingC.escapedD.Have escaped
Why did Shaefer put the paper under glass?A) To prevent Rosa from feeling the print.B) To stop the reflection of heat.C) To make things as difficult as possible.D) To stop her from cheating.
23． From the passage，we can know it is ________for plants to grow in dry places．A． easyB． difficultC． impossibleD． important
29． Why are green plants and grass helpful?A． Because they can hold the water．B． Because they can stop the wind from blowing the earth away．C． Because they can keep the earth wet．D．All the above．
The fact that a part of the cargo has already been discharged will not ________ the owners of the rest， under all circumstances， from claiming a general average contribution from the Shipowner．A.precludeB.includeC.diluteD.pollute
Both the Shipowner and the Charterer will be discharged from their obligations under the charter-party if it ______ frustrated．A.providesB.becomesC.containsD.comes
Before personnel are lifted from a vessel in a personnel basket, the vessel should be ______.A.directly under the boomB.moving away from the boomC.stopped dead in the waterD.tied ti the boom
What is suggested about the engineers from London?A.They are new to the Dawson companyB.Bertrand Fournier is their immediate supervisorC.They have visited the Valbonne plant beforeD.They recently inspected the Geneva and Warsaw plants
He believes that from a military standpoint,the situation is under control.A:positionB:point of viewC:knowledgeD:argument
He ventured that plants draw part of their nourishment from the air.A:dared B:endangeredC:agreed D:prevented
What is the correct procedure for adding an access point in WCS？（）A、Choose Configure Access_Point， then enter the AP MAC addressB、Choose Configure Access_Point， then enter the IP address of the APC、Wait until the WLC downloads its code from the WCS and choose the access point from the list under the WLC option of the Configure menuD、Wait until the AP downloads its code from the WCS and choose the access point from the list under the Access_Point option of the Configure menu
The partial loss of or damage to the cargo is not recoverable from the insurer resulting from natural calamities under（）in PICC Ocean Marine Cargo Clauses.A、All RisksB、FPAC、WAD、All Risks+War Risks
In the SSCT， when you need to see the Channel Prices， what is the right action to take？（）A、Download the BP version of SSCT from PartnerWorldB、Enter the IBM authorized password in SSCT under User Access Level menuC、Get the country price list from your country BP organization and import into SSCTD、Apply the country channel discounts under the Quote menu choosing the Discount/Uplift option
An administrator is looking for the "Open Restricted Shell Terminal" option on the HMC GUI. Under which panel is this option available？（） A、HMC Management， but only from a local connectionB、Service Management， but only from a local connection.C、Systems Management， but only from a local connection.D、Systems Management， but only from a remote connection.
An administrator is looking for the "Open RestrictedShell Terminal" option on the HMC GUI. Under which panel is this option available?（）A、HMC Management, but only from a local connection.B、Service Management, but only from a local connection.C、Systems Management, but only from a local connection.D、Systems Management, but only from a remote connection.
单选题The passage warns of which of the following dangers?ACompanies in the United States may receive no protection from imports unless they actively seek protection from import competition.BCompanies that seek legal protection from import competition may incur legal costs that far exceed any possible gain.CCompanies that are United States owned but operate internationally may not be eligible for protection from import competition under the laws of the countries in which their plants operate.DCompanies that are not United States owned may seek legal protection from import competition under United States import relief laws.
单选题As Chief Officer of a vessel underway，it comes to your attention that the vessel is，in some manner，unseaworthy. Under such circumstances the Master is required to take action upon receiving（）.Ainformation of such condition from yourselfBnotification of such condition from yourself and the Second OfficerCnotification of such condition from yourself and any other member of the crewDnotification of such condition from yourself or the Second Officer
多选题Consider each of the choices separately and select all that apply. Which of these can be inferred from the fact that the French built orangeries for certain tropical plants?AGreenhouses may be used to keep plants at a moderate temperatureBThe climate of France is unsuited to growing tropical plants outdoors.CLouis ⅩⅣ was a frequent and enthusiastic traveler to Africa and Asia
单选题Before personnel are lifted from a vessel in a personnel basket，the vessel should be（）.Adirectly under the boomBmoving away from the boomCstopped dead in the waterDtied to the boom