51. 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

52 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  49.C  50.D  51.C  52.B

Passage 9

(09·重庆C篇)

Sports can help you keep fit and get in touch with nature .However, whether you are on the mountains, in the waves, or on the grassland, you should be aware that your sport of choice might have great influence on the environment.

Some sports are resource-hungry. Golf, as you may know, eats up not only large areas of countryside, but also tons of water. Besides, all sorts of chemicals and huge amounts of energy are used to keep its courses(球场) in good condition. This causes major environmental effects. For example, in the dry regions of Portugal and Spain, golf is often held responsible for serious water shortage in some local areas.

There are many environment-friendly sports. Power walking is one of them that you could take up today. You don’t need any special equipment except a good pair of shoes; and you don’t have to worry about resources and your purse. Simple and free, power walking can also keep you fit. If you walk regularly, it will be good for your heart and bones. Experts say that 20 minutes of power walking daily can make you feel less anxious, sleep well and have better weight control.

Whatever sport you take up, you can make it greener by using environment-friendly equipment and buying products made from recycled materials. But the final goal should be “green gyms”. They are better replacements for traditional health clubs and modern sports centers. Members of green gyms play sports outdoors, in the countryside or other open spaces. There is no special requirement for you to start your membership. And best of all, it’s free.

55. What would be the best title for the passage?

A. Drinking for Better Social Relationships.

B. Experiments of Personality Evaluation.

C. Developing Better Drinking Habits.

D. Physical Sensations and Emotions.

答案  51.C  52.B  53.A  54.C  55.D

Passage 8

(09·浙江C篇)

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 insets, 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 detect 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 than can house

Thousands of plants.

   The research team worked with an e-nose than 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 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 Dudareva, 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.

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