For the first time, researchers have discovered that some plants can kill insect
题型：不详难度：来源：
For the first time, researchers have discovered that some plants can kill insects in order to get additional nutrients. New research shows that they catch and kill small insects with their own sticky hairs near the roots and then absorb nutrients through their roots when the insects are killed and fall to the ground.
Professor Mark Chase, of Kew and Queen Mary, University of London, said: “The cultivated (改良的) tomatoes and potatoes still have the hairs. Tomatoes in particular are covered with these sticky hairs. They do trap small insects on a regular basis. They do kill insects.”
The number of these carnivorous plants is thought to have came up to 50 percent and many of them have until now been wrongly regarded as among the most harmless plants. Among them are species of petunia(矮牵牛), some special tobacco plants and cabbages, some varieties of potatoes and tomatoes, etc. Researchers at Royal Botanical Gardens Kew, which carried out the study, now believe there are hundreds more killer plants than previously realized.
It is thought that the technique was developed in the wild to get necessary nutrients in poor quality soil and even various plants grown in your vegetable garden still have the ability.
The researchers, publishing their finding in the Botanical Journal of the Linnean Society, said: “We may be surrounded by many more murderous plants than we think.” “We are accustomed to thinking of plants as being immobile and harmless, and there is something deeply frightening about the thought of meateating plants，” they added.
小题1:Tomatoes and potatoes kill insects to ________.| A．get more sticky hairs | | B．make themselves grow better | | C．make their roots stronger | | D．avoid falling down to the ground |
小题2:The word “carnivorous” in Paragraph 3 most probably means ________.| A．fastgrowing | B．harmless | | C．insectkilling | D．nutritious |
小题3:The insectkilling technique of vegetables is developed most probably through ________.| A．evolution of species | | B．helps from other garden plants | | C．artificial cultivation | | D．nutrients preserved in rich soil |
小题4:The text is probably taken from ________.| A．a student book | B．a science fiction | | C．a scientific repot | D．a bulletin board |
|
答案
小题1:B
小题2:C
小题3:A
小题4:C |
解析
文章大意：最新研究发现：为了获得营养，很多植物都是昆虫***手。
小题1:B 细节理解题。由第一段第一句话“...some plants can kill insects in order to get additional nutrients.”可知，这些植物***手***死昆虫的目的是获得营养，当然是为了让它们自己长得更好。
小题2:C 猜测词义题。由划线词前面的these可知，此处指的是前面提到的“***死昆虫”的植物。
小题3:A 细节理解题。由第四段“It is thought that the technique was developed in the wild to get necessary nutrients in poor quality soil”可知，植物的这种技能是长期物种进化的结果
小题4:C 推理判断题。由文章第一段“For the first time, researchers have discovered that...”和最后一段“The researchers, publishing their finding in the Botanical Journal of the Linnean Society...”可推知，本文是一篇科学研究报告。 |
举一反三
Seven species of carp(鲤鱼) native to Asia have been introduced into United States waters in recent decades, but it"s four in particular－bighead, black, grass and silver－that worry ecologists, biologists, fishers and policymakers alike. Introduced in the southeast to help control weeds and parasites in aquaculture (水产养殖) operations, these fish soon spread up the Mississippi River system where they have been crowding out native fish populations not used to competing with such aggressive invaders. The carps" presence in such numbers is also harming water quality and killing off sensitive species.
Asian carp are strong to jump over barriers such as low dams. They lay hundreds of thousands of eggs at a time and spread into new habitat quickly and easily. Also, flooding has helped the fish expand into previously unattainable water bodies. And fishers using young carp as live bait have also helped the fish"s spread, as they have boats going through locks up and down the Mississippi.
The federal government considers the Asian carps to be annoying species and encourages and supports “active control” by natural resources management agencies. Federal and state governments have spent millions in tax dollars to prevent the carp from making their way into the Great Lakes, but an underwater electric fence constructed to keep them out has not worked as well as hoped, and policymakers are reviewing other options now.
In the meantime, state and federal agencies are monitoring the Mississippi and its branches for Asian carp and testing various barrier technologies to prevent their further spread. For instance, the National Park Service is cooperating with the state of Minnesota"s Department of Natural Resources to construct new dams that are high enough to prevent Asian carp from jumping over. The Asian Carp Regional Coordinating Committee has funded DNA monitoring in potentially affected water bodies whereby researchers can determine whether the troublesome fish are present just by the biological footprints they leave behind. Individuals can do their part by not transporting fish, bait or even water from one water body to another, and by emptying and washing boats before moving them between different water bodies.
小题1:Asian carp have been introduced to the USA in order to ________.| A．improve water quality | | B．help sensitive species | | C．control the number of native fishes | | D．control the ecosystem in aquaculture |
小题2:The measure to keep Asian carp out of the Great Lake but proved not good is ________.| A．testing various barrier technologies | | B．construction of an underwater electric fence | | C．Emptying and washing boats before using them. | | D．monitoring the Mississippi and its branches for Asian carp |
小题3:It is suggested from the passage that ________.| A．aquaculture operations are dangerous to the water bodies | | B．scientific technology is useless in preventing Asian carp spreading | | C．both the state and the individuals can make efforts to keep out Asian carp | | D．Asian carp have successfully invaded the Mississippi and the Great Lakes |
|
In her new book, “The Smartest Kids in the World”， Amanda Ripley, an investigative journalist, tells the story of Tom, a highschool student from Gettysburg, Pennsylvania, who decides to spend his senior year in Wroclaw, Poland. Poland is a surprising educational success story: in the past decade, the country raised students" test scores from significantly below average to well above it. Polish kids have now outscored American kids in math and science, even though Poland spends, on average, less than half as much per student as the United States does. One of the most striking differences between the high school Tom attended in Gettysburg and the one he ends up at in Wroclaw is that the latter has no football team or teams of any kind.
That American high schools spend more time and money on sports than on math is an old complaint. In December, when the latest Program for International Student Assessment (PISA) results are announced, it"s safe to predict that American highschool students will once again show their limited skills in math and reading, outscored not just by students in Poland but also by students in places like China, Finland, Singapore, and Japan. Meanwhile, they will have played some very exciting football games, which will have been breathlessly written up in their hometown papers.
Why does this situation continue? Well, for one thing, kids like it. And for another, according to Ripley, parents seem to like the arrangement, too. She describes a tour she took of a school in Washington D．C., which costs thirty thousand dollars a year. The tour leader a mother with three children in the school was asked about the school"s flaws (瑕疵). When she said that the math program was weak, none of the parents taking the tour reacted. When she said that the football program was weak, the parents suddenly became concerned. “Really？” one of them asked worriedly, “What do you mean？”
One of the ironies of the situation is that sports show what is possible. American kids" performance on the field shows just how well they can do when expectations are high. It"s too bad that their_test_scores_show_the_same_thing._
小题1:Tom decides to spend his senior year in Poland because ________.| A．he intends to improve his scores | | B．Polish kids are better at learning | | C．sports are not supported at schools in Gettysburg | | D．he wants to be the smartest kid in the world |
小题2:According to Paragraph 2, we know that ________.| A．PISA plays a very important role in America | | B．little time is spent on sports in Japanese schools | | C．American students do better in both math and sports | | D．too much importance is placed on sports in America |
小题3:The underlined sentence in the last paragraph means ________.| A．low expectations result in American students" poor PISA performance | | B．high expectations push up American students" academic performance | | C．American students" academic performance worries their parents a lot | | D．lacking practice contributes to American students" average performance |
小题4:The purpose of this article is to ________.| A．compare Polish schools with those in America | | B．call on American schools to learn from the Polish model | | C．draw public attention to a weakness in American school tradition | | D．explain what is wrong with American schools and provide solutions |
|
I lost my sight when I was four years old by falling off a box car in a yard in Atlantic City and landing on my head.Now I am thirtytwo.I can ____ remember the brightness of sunshine and what red color is.It would be wonderful to see again, ____ a disaster can do strange things to people.
It occurred to me the other day that I might not have come to ____ life as I do if I hadn"t been blind. I believe in life now.I am not so sure that I would have believed in it so deeply, ____. I don"t mean that I would prefer to go without my eyes. I simply mean that the loss of them made me ____ the more what I had left.
The hardest lesson I had to learn was to believe in myself.That was ____. If I hadn"t been able to do that, I would have ____ and become a chair rocker for the rest of my life.When I say ____ in myself I am not talking about simply the kind of selfconfidence that helps me down a(n) ____ staircase alone.That is part of it.But I mean something ____ than that: an assurance that there is a special place where I can make myself fit.
It took me years to discover and ____ this assurance.It had to start with the most elementary things.Once a man gave me an indoor baseball, I thought he was laughing at me and I was ____.“I can"t use this，” “I said. Take it with you；” he ____ me.“and roll it around.” The words ____ in my head. “Roll it around！” By rolling the ball I could ____ where it went.This gave me an idea how to achieve a goal I had thought ____： playing baseball.At Philadelphia"s Overbrook School for the Blind I ____ a successful variation of baseball. We called it ground ball.
All my life I have set ahead of me a series of ____ and then tried to reach them, one at a time.I had to learn my ____. It was no good trying for something I knew at the start was wildly out of reach because that only invited the bitterness of failure. I would fail sometimes anyway but on the average I made ____.
| 小题1: | | A．entirely | B．nearly | | C．vaguely | D．simply |
|
| 小题3: | | A．assess | B．fear | | C．enrich | D．love |
|
| 小题4: | | A．otherwise | B．therefore | | C．however | D．besides |
|
| 小题5: | | A．understand | B．appreciate | | C．possess | D．accept |
|
| 小题6: | | A．enough | B．specific | | C．tough | D．basic |
|
| 小题7: | | A．survived | B．escaped | | C．collapsed | D．sacrificed |
|
| 小题8: | | A．hope | B．power | | C．courage | D．belief |
|
| 小题9: | | A．unfamiliar | B．unbelievable | | C．unexpected | D．uncomfortable |
|
| 小题10: | | A．harder | B．bigger | | C．warmer | D．heavier |
|
| 小题11: | | A．weaken | B．strengthen | | C．sharpen | D．brighten |
|
| 小题12: | | A．upset | B．flattered | | C．ashamed | D．hurt |
|
| 小题13: | | A．urged | B．promised | | C．convinced | D．advised |
|
| 小题14: | | A．flashed | B．appeared | | C．stuck | D．crowded |
|
| 小题15: | | A．notice | B．hear | | C．smell | D．touch |
|
| 小题16: | | A．impossible | B．important | | C．imaginary | D．impressive |
|
| 小题17: | | A．produced | B．imitated | | C．invented | D．spotted |
|
| 小题18: | | A．goals | B．efforts | | C．directions | D．barriers |
|
| 小题19: | | A．challenges | B．strengths | | C．situations | D．limitations |
|
| 小题20: | | A．history | B．change | | C．progress | D．sense |
|
|
Password (密码) strength has been a topic about the Internet lately. I have seen lots of clever methods for generating and remembering strong passwords. Some are better than others, but in my opinion, none are adequate. Here"s the problem: It doesn"t matter how strong your passwords are if you use the same one on multiple sites. All it takes is for a site to get hacked(侵入), like Gawker media, or even Sony did, and now your superstrong password has been stolen, and every site on which you used that password has been accessed.
So, the bottom line is that no matter how strong your passwords are, and no matter what clever tricks you use to help you remember them, if you surf internet often, the only truly secure password system is what you need.
Enter LastPass. It"s not the only password manager out there, but I like it the best. You create ONE strong password that you have to memorize and use it to access your LastPass database. The LastPass database is stored online, on LastPass"s servers. LastPass recognizes the site you"re on and automatically logs you in (after, optionally, asking you to reenter your master password). LastPass also has automatic form fill and automatic password generation. This means that you can have a different, unique, very strong password for every site you log into, but you only have to remember one master password. It"s the best of both worlds.
One argument against LastPass is that if their database is attacked, then all of your sites are in danger, and that"s true, but given that their entire line of work is keeping that information safe, I"m willing to take that chance. The alternative is rolling dice(掷骰子) or picking phrases to create passwords, writing all of them down on a piece of paper or something, and then having to manually type them in when I go to a site. A terrible mess.
There is a free version of LastPass, with some additional features unlocked if you pay a $12 a year subscription.
Joshua Bardwell
小题1:The writer thinks using the same password everywhere is ________.| A．dangerous | B．convenient | | C．appropriate | D．adequate |
小题2:When using Lastpass, users have to remember ________.| A．all passwords used | | B．the last password | | C．unique password each time | | D．the master password only |
小题3:Critics are against Lastpass because ________.| A．they have better ways to create password | | B．they think rolling dice is more convenient | | C．they have no faith in Lastpass database"s safety | | D．Gawker media and Lastpass were hacked once |
小题4:Joshua Bardwell writes the passage to ________.| A．share his experience | | B．introduce a product of good quality | | C．advertise his product | | D．teach how to use a new product |
|
Nuclear power"s danger to health, safety, and even life itself can be summed up in one word: radiation.
Nuclear radiation has a certain mystery about it, partly because it cannot be detected by human senses. It can"t be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around us but we can"t detect them, sense them, without a radio receiver. Similarly, we can"t sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things.
At very high levels, radiation can kill an animal or human being immediately by killing masses of cells in vital organs. But even the lowest levels can do serious damage. There is no levels of radiation that is completely safe. If the radiation does not hit anything important, the damage may not be serious. This is the case when only a few cells are hit, and if they are killed immediately. Your body will replace the dead cells with healthy ones. But if the few cells are only damaged, and if they reproduce themselves, you may be in trouble. They can grow into cancer. Sometimes this does not show up for many years.
This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the victim being aware at the time that damage has occurred. A person can be irradiated(辐射)and feel fine, then die for cancer five, ten, or twenty years later as a result. Or a child can be born weak as a result of radiation absorbed by its grandparents.
Radiation can hurt us. We must know the truth.
小题1:Which of the following statements is true?| A．Nuclear radiation is just like common radio waves. | | B．Nuclear radiation can cause cancer to human beings. | | C．Nuclear radiation can be detected by human senses. | | D．Nuclear radiation can be safe to human beings if its level is low. |
小题2:How can nuclear radiation kill an animal?| A．By damaging its heart. | | B．By killing a few cells. | | C．By hitting any place in its body. | | D．By killing many cells in important organs. |
小题3:If a human being is hit by nuclear radiation, he may __________.| A．die of cancer after many years | | B．die immediately | | C．have a child who may be born weak | | D．all of the above |
|
最新试题
热门考点