题目内容

 

Plants 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.

1.We learn from the text that plants communicate with each other by______.

A. making some sounds    B. waving their leaves

C. producing some chemicals D. sending out electronic signals

2.What did the scientists do to find out if the e-nose worked?

A. They presented it with all common crops..

B. They fixed 13 sensors inside the device.

C. They collected different damaged leaves.

D. They made tests on damaged and healthy leaves.

3.According to the writer, the most amazing thing about the e –nose is that it can ______.

A. pick out ripe fruits

B. spot the insects quickly

C. distinguish different damages to the leaves

D. recognize unhealthy tomato leaves

4.We can infer from the last paragraph that the e-nose_____.

A. is unable to tell the smell of flowers

B. is not yet used in greenhouses

C. is designed by scientists at Purdue

D. is helpful in killing harmful insects

 

【答案】

1.C

【解析】细节判断题。由Instead, plants produce volatile compounds, chemicals that easily change from a liquid to a gas可以知道答案。

2.D

【解析】推理判断题。由第五段话可以知道在测试e-nose 的时候既有healthy leaves也有damaged leaves。所以答案为:D。

3.C。

【解析】细节判断题。由倒数第二段话最后两行可以知道答案。

4.B。

【解析】推理判断题。由最后一段最后一句可以知道答案:Hopefully, scientists believe, the device could bring large benefits to greenhouse managers in the near future。

 

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One reaction to all the concern about tropical deforestation(毁林) is a blank stare that asks the question, "Since I don't live there, what does it have to do with me?"

The answer is that your way of life, wherever you live in the world, is tied to the tropics in many ways. If you live in a house, wash your hair, eat fruits and vegetables, drink soda, or drive a car, you can be certain that you are affected by the loss of tropical forests.

Biologically, we are losing the richest regions on earth when, each minute, a piece of tropical forest, the size of ten city blocks, disappears. As many as five million species of plants, animals, and insects (40 to 50 percent of all living things) live there, and are being lost faster than they can be found and described. Their loss is immeasurable.

Take rubber for example. For many uses, only natural rubber from trees will do. Synthetics are not good enough. Today over half the world's commercial rubber is produced in Malaysia and Indonesia, while the Amazon's rubber industry produces much of the world's four million tons. And rubber is an important material in making gloves, balloons, footwear and many sporting goods. Thousands of other tropical plants are valuable for their industrial use.

Many scientists strongly believe that deforestation contributes to the greenhouse effect -- or heating of the earth from increased carbon dioxide in the atmosphere. As we destroy forests, we lose their ability to change carbon dioxide into oxygen.

Carbon dioxide levels could double within the next half-century, warming the earth by as much as 4.5 degrees. The result? A partial melt-down of polar ice caps, raising sea levels as much as 24 feet; even 15 feet could threaten anyone living within 35 miles of the coast. Unbelievable? Maybe. But scientists warn that by the time we realise the severe effects of tropical deforestation, it will be 20 years too late.

Can tropical deforestation affect our everyday lives? Now, you should have got the answer.

1.The underlined word "synthetics" probably means_________.

A. natural rubber                   B. tropical materials

C. man-made material               D. commercial rubber

2.According to the passage, which of the following is NOT true?

A. The forests are losing their function in turning carbon dioxide into oxygen.

B. Many of our daily uses are related to the tropical forests.

C. Tropical plants can be used to make industrial products.

D. High carbon dioxide levels will make the earth warmer.

3.The author's attitude towards the tropical deforestation is _________ .

A. puzzling        B. cold          C. supporting        D. opposed

4.Which of the following might be the best title for the passage?

A. Tropical Forests                 B. The Value of Tropical Forests

C. Tropical Forests and Our Life     D. The Greenhouse Effects

 

Plants have family values, too; it seems, with new research suggesting they can recognize close relatives in order to work together.

An ability to tell family from strangers is well known in animals, allowing them to cooperate and share resources, but plants may possess similar social skills, scientists believe.

Susan Dudley and Amanda File of McMaster University in Ontario, Canada, report they have demonstrated for the first time that plants can recognize their kin.

This suggests that plants, though lacking recognition and memory, are capable of complex social interactions.

“Plants have this kind of hidden but complicated social life,” Dudley said.

The study found plants from the same species of beach­-dwelling wildflower grew aggressively alongside unrelated neighbors but were less competitive when they shared soil with their families.

Sea rocket, a North American species, showed stronger and healthier root growth when planted in pots with strangers than when raised with relatives from the same maternal(母系的) family, the study found.

This is an example of kin selection, a behavior common in animals in which closely related individuals take a group approach to succeeding in their environment, the researchers said.

Kin selection also applies to competition, because if family members compete less with each other, the group will do better overall. “Everywhere you look, plants are growing right up next to other plants,” Dudley said,“ Usually it’s a case of each plant for itself. But sometimes those plants are related, and there are benefits to not wasting resources on being competitive, and there is not really a cost to not being competitive as long as your neighbor is also not being competitive.”

Learning and memory appear to be important for kin recognition in animals, but this isn’t an option for plants, she noted.

Some researchers speculate(猜测) that plants communicate through their roots, identifying themselves using tiny chemical signatures specific to each plant’s family.

1.What’s the main idea of the message?

A.Studies find plants can recognize, communicate with relatives.

B.Kin selection is important for plants.

C.Animals can recognize and memorize their relatives.

D.Competition asks plants to recognize their relatives.

2.Which of the following is NOT right about animals’ social skill?

A.Animals can recognize and memorize their relatives.

B.Animals’ social skill is to cooperate and share resources.

C.Animals’ social skill can recognize close relatives in order to work together.

D.Animals’ social skill is no use at all.

3.Plants’ kin selection is to ________.

A.grow well                             B.compete with other kinds of plants

C.strengthen the relationship among siblings    D.find which one is the best

4.From the passage,we learn that ________.

A.sea rocket is a South American species

B.sea rocket grows aggressively alongside unrelated neighbors

C.sea rocket grows aggressively alongside its siblings

D.sea rocket is a kind of bush without flowers

5.How can the plants communicate with each other according to experts’ suppose?

A.Plants communicate by using tiny chemical signatures specific to each plant’s family.

B.Plants communicate with each other through their roots.

C.Plants communicate with each other by their leaves.

D.Plants communicate with each other with their flowers.

 

The light from the campfire brightened the darkness, but it could not prevent the damp cold of Dennis’s Swamp (沼泽地) creeping into their bones. It was a strange place. Martin and Tom wished that they had not accepted Jack’s dare. They liked camping, but not near this swamp.

“So,” Martin asked as they sat watching the hot coals. “How did this place get its name?”

“Are you sure you want to hear it ? It’s a scary story,” warned Jack.

“Of course!” cried out Tom. “If there were anything to be scared of, you wouldn’t have chosen this place!”

“Ok, but don’t say I didn’t warn you,” said Jack, and he began this tale.

“Way back in time, a man called Dennis tried to start a farm here. He built that cottage over there to live in. In those days, the area looked quite different ---- it was covered with tall trees and the swamp was a crystal-clear river. After three hard years, Dennis had cleared several fields and planted crops. He was so proud of his success that he refused to listen to advice.

“‘You are clearing too much land,’ warned one old man. ‘ The land is a living thing. It will hit back at you if you abuse it. ’

“‘Silly fool,’ said Dennis to himself. ‘If I clear more land, I can grow more crops. I’ll become wealthier. He’s just jealous!’”

“Dennis continued to chop down trees. Small animals that relied on them for food and shelter were destroyed. He was so eager to expand his farm that he did not notice the river flowing slowly towards his door. He did not notice salt seeping to the surface of the land. He did not notice swamp plants choking all the native plants.”

“What happened?” Martin asked. It was growing colder. He trembled, twisting his body closer to the fire.

“The land hit back ---- just as the old man warned,” Jack shrugged. “Dennis disappeared. Old folks around here believe that swamp plants moved up from the river and dragged him underwater. His body was never found.”

“What a stupid story,” laughed Tom. “Plants can’t …” Before he had finished speaking, he screamed and fainted (晕倒). The other two boys jumped up with fright, staring at Tom. Suddenly, they burst out laughing. Some green swamp ivy (常春藤) had covered Tom’s face. It was a while before Tom could appreciate the joke.

1.The underlined word “dare” in Paragraph 1 is closed in meaning to ________.

A.courage          B.assistance         C.instruction         D.challenge

2.Why did Jack tell Tom and Martin the story?

A.To frighten them.

B.To satisfy their curiosity.

C.To warn them of the danger of the place.

D.To persuade them to camp in the swamp.

3.Why did Dennis ignore the warning of the old man?

A.The old man envied him.                  B.The old man was foolish

C.He was too busy to listen to others.          D.He was greedy for more crops.

4.Why did Tom scream and faint?

A.He saw Dennis’s shadow                 B.He was scared by a plant

C.His friends played a joke on him.            D.The weather became extremely cold.

5.What lesson can we learn from the story of Dennis?

A.Grasp all, lose all

B.No sweat, no sweet.

C.It is no use crying over spilt milk

D.He who makes no mistakes makes nothing.

 

“If you talk to the plants, they will grow faster and the effect is even better if you’re a woman.” Researchers at Royal Horticultural Society carried out an experiment to find that the voice of a woman gardener makes plants grow faster.

   The experiment lasted a month and by the end of the study scientists managed to discover that tomato plants grew up two inches taller when women gardeners talked to them instead of male.

   Sarah Darwin was the one making the plants the best growth. Her voice was the most “inspiring” for plants than those of nine other gardeners when reading a passage from The Origin of Species. The great-great-granddaughter of the famous botanist (植物学家)Charles Darwin found that her plant grew about two inches taller than the plant of the best male gardener.

   Colin Crosbie, Garden Superintendent at RHS, said that the finding cannot yet be explained.He says that women have a greater range of pitch and tone(音高和音色)which might have a certain effect on the sound waves that reach the plant. “Sound waves are an environmental effect just like rain or light ,”said Mr Grosbie.

The study began in April at RHS Garden Wisley in Survey. Scientists started with open auditions(听力) for the people who were asked to record passages from John Wyndham's The Day of the Triffids, Shakespeare’s A Midsummer's Night Dream and Darwin's The Origin of Species.

Afterwards researchers selected a number of different voices and played them to 10 tomato plants during a period of a month. Each plant had headphones connected to it. Through the headphones the sound waves could hit the plants. It was discovered that plants that “listened” to female voices grew taller by an inch in comparison to plants that heard male voices.

1.What does the passage talk about?

   A. Plants enjoy men’s voices than women’s.

   B. A science experiment in a museum.

   C. Voice’s influence on plant growing.

   D. Strange findings at Royal Horticultural Society.

2.What does the underlined sentence in paragraph 4 mean?

    A. Plants need sound as well as rain and light.

    B. Sound is basic for the plant to grow.

    C. Sound has a good effect as rain or light does.

D. Plants can’t live without sound, rain or light.

3.What can we learn from the passage?

    A. The experiment ended in May.  

B. Scientist can explain the findings clearly.

    C. Plants enjoy listening to the passages from famous works.

D. The findings are of great importance to human beings.

 

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