题目内容

When a leafy plant is under attack, it doesn’t sit quietly. Back in 1983, two scientists, Jack Schultz and Ian Baldwin, reported that young maple trees getting bitten by insects send out a special smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be a warning. What the plants pump through the air is a mixture of chemicals known as volatile organic compounds(VOCs).

Scientists have found that all kinds of plants give out VOCs when being attacked. It’s a plant’s way of crying out. But is anyone listening? Obviously. Because we can watch the neighbors’ react.

Some plants pump out smelly chemicals to keep insects away. But others do double duty. They pump out perfumes to attract different insects who are their natural enemies. Once the insects arrive, the tables are turned. The attacker who was lunching now becomes lunch.

In study after study, it appears that these chemical conversations help the neighbors. The damage is usually more serious on the first plant, but the neighbors stay safer because they heard the warning and knew what to do.

Does this mean that plants talk to each other? Scientists don’t know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in fact, was talking to itself. Perhaps the neighbors just happened to hear the cry by accident and so wrong information was exchanged.

Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate than the world we can see and hear, our senses are weak. There’s a whole lot going on.

1.What does a plant do when it is under attack?

A.It makes noises. B.It gets help from other plants.

C.It stands quietly. D.It sends out certain chemicals.

2.What does “the tables are turned” mean in Paragraph 3?

A.The attackers are attacked. B.The insects gather under the table.

C.The plants get ready to fight back. D.The perfumes attract natural enemies.

3.Scientists find from their studies that plants can__________.

A.talk to one another B.predict natural disasters

C.protect themselves against insects D.help their neighbors when necessary

4.What can we learn from the last paragraph?

A.The world is changing faster than ever. B.People have stronger senses than before.

C.The world is more colorful than it seems. D.People in Darwin’s time were full of imagination.

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下面文章中有五处需要添加小标题。请从以下选项(A、B、C、D、E和F)中选出符合各段意思的小标题。选项中有一项是多余项。

A. Places to Stay B. Places to Visit C. Weather

D. Shopping E. History F. Restaurants

Savannah City Guide

1.

If you want to spend the night in Savannah, you have lots of place to choose from. You can stay at a big hotel a small inn, or a comfortable motel. Savannah's hotels, motels and inns are famous for their friendly service. Call one of these places to make your reservation.

2.

Savannah is well known for its wonderful restaurants Many restaurant serve local, seafood or old-fashioned Southern food. The following are sonic of the best restaurants in the area.

3.

If you like to shop, Savannah is the place for you! You'll find all kind of stores in Savannah. You can go shopping in small stores or big shopping malls. Are you looking for a special treasure or a great deal? You'll find it in Savannah.

4.

There are so many things to do and see in Savannah. The sightseeing is great. You can visit beautiful historic homes and museums. You can take a boat tour or visit Civil War forts. With all of Savannah's history, art, and beautiful buildings, be sure to take the time to enjoy all that Savannah has to offer!

5.

Savannah has lots of sunshine throughout the year. Summer are hot and humid. Winters are generally mild. Temperatures usually range between 30 degrees Fahrenheit (-1 degree Centigrade) and 90 degrees Fahrenheit (33 degrees Centigrade).

Uncle Sam

Do your children enjoy interesting stories, funny games and exciting dances? Uncle Sam will be read to teach children of all ages all these things at the City. Theatre on Saturday morning at 10:00. Free.

Walking Tour

Forget your worries on Saturday morning. Take a beautiful walk and learn about local history. Meet at the front entrance of City Hall at 9:30. Wear comfortable shoes!

Movie Time

Two films will be shown on Saturday afternoon at the Museum Theatre. See March of the Penguins at 1:30. Kung Fu Panda will be at 3:45. For further information, call 4987898.

International Picnic

Are you tired of eating the same food every day? Come to Central Park on Saturday and enjoy food from all over the world. Delicious and not expensive. Noon to 5:00 p.m.

Take Me Out to the Ballgame

It's October, and this Saturday night is your last chance to see the Redbirds this year. Get your tickets at the gate. It might be cold. Don't forget sweaters and jackets.

Do You Want to Hear The Zoo?

The Zoo, a popular rock group from Australia, will give their first US concert this Saturday night at 8:00 at Rose Hall, City College.

1.You probably eat Chinese, Italian and Indian food at _______.

A.City Hall B.Central Park C.the City Theatre

2.We can see movies at _______.

A.10:00 a.m. B.9:30 a.m. C.3:45 p.m.

3.The Zoo here is a ________.

A.Music group B.US concert C.Popular park

4.From the passage, we can know_________.

A.if you are 8 years old, you have to pay to learn exciting dances

B.you can learn local history on a walking tour on Sunday morning

C.The Redbirds' last match this year will be held outside

5.The passage is mainly about_________.

A.city news B.weekend activities C.music week

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