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C
Let These Plants Swat the Bugs for You
Some plants get so hungry they eat flies, spiders, and even small frogs. What’s more amazing is that these plants occur naturally (in special environments) in every state. In fact, they’re found on every continent except Antarctica.
You’ve probably seen a Venus’ flytrap. It’s often sold in museum gift stores, department stores, and even supermarkets. A small plant, it grows 6 to 8 inches tall in a container. At the end of its stalks(莖)are specially modified leaves that act like traps. Inside each trap is a lining of tiny trigger(觸發(fā))hairs. When an insect lands on them, the trap suddenly shut. Over the course of a week or so, the plant feeds on its catch.
The Venus’ flytrap is just one of more than 500 species of meat-eating plants, says Barry Meyers-Rice, the editor of the International Carnivorous Plant Society’s Newsletter. Note: Despite any science-fiction stories(科幻小說)you might have read, no meat-eating plant does any danger to humans.
Dr. Meyers-Rice says a plant is meat-eating, only if it does all four of the following: “attract, kill, digest, and absorb” some form of insects , including flies, butterflies, and moths. Meat-eating plants look and act like other green plants—well, most of the time.
All green plants make sugar through a process called photosynthesis(光合作用). Plants use the sugar to make food. What makes “meat-eating” plants different is their bug-catching leaves. They need insects for one reason: nitrogen(氮). Nitrogen is a nutrient that they can’t obtain any other way. Why?
Almost all green plants on our planet get nitrogen from the soil. “Meat-eating” plants can’t. They live in places where nutrients are hard or almost impossible to get from the soil because of its acidity(酸度). So they’ve come to rely on getting nitrogen from insects and small animals. In fact, nutrient-rich soil is poisonous to “meat-eating” plants. Never fertilize(施肥)them! But don’t worry, either, if they never seem to catch any insects. They can survive, but they’ll grow very slowly.
64. Venus flytrap      
A. is a small plant which grows in a container. 
B. is a kind of plant which gets hungry easily.
C. can attract, kill, digest and absorb some form of insects.
D. grows 6-8 inches tall  
65. From the passage, we know      .
A. “meat-eating” plants are found on every continent.
B. all green plants get nitrogen from the soil.
C. bug-catching leaves make “meat-eating” different from other plants.
D. some “meat-eating” plants in the rainforest do danger to humans.
66. “Meat-eating” plants grow very slowly,      .
A. so you’d better fertilize them   
B. probably because the source of nitrogen is cut off.
C. simply because they can’t absorb nitrogen from the soil 
D. and then they will die slowly.
67. Which of the following is true?
A. “Meat-eating” plants look and act like other green plants.
B. No insects, no “meat-eating” plants.
C. The reason why Venus flytrap needs flies is that it needs to get nutrient from them.
D. Green plants make sugar at night.
68. What does the underlined word nutrient in paragraph 5 probably mean?
A. 化學(xué)物    B.營養(yǎng)物    C. 肥料      D. 氮?dú)浠衔?/p>


64---68    CCBCB    

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