Some plants get so hungry they eat flies, 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 -- a small plant, which grows 6 to 8 inches tall in a container. At the end of its stalks (茎) are leaves that act like traps (陷阱). Inside each trap is a lining of tiny hairs. When an insect lands on them, the traps 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. He states although you might have read some science-fiction stories, no meat-eating plant does any danger to humans.
Barry says a plant is meat-eating, only if it does all four of the following: "attract, kill, digest, and absorb" some form of insects. Meat-eating plants look and act like other green plants -- well, most of the time.
All green plants make sugar to produce food. What makes meat-eating plants different is their special leaves, which 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 to get from the soil because of its acidity. So they've come to rely on getting nitrogen from insects and small animals. In fact, nutrient-rich soft 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.
小题1:According to the passage, a Venus' flytrap ______.
A．is a small plant which grows in a container
B．is a kind of plant which gets hungry easily
C．can trap and feed on some form of insects
D．can only grow 6-8 inches tall小题2:From the passage, we can infer that ______.
A．meat-eating plants are found nowhere else except Antarctica
B．all green plants get nitrogen from the soil
C．meat-eating plants endanger humans in science-fiction stories
D．the nutrient-poor soil is beneficial to meat-eating plants小题3:Meat-eating plants grow very slowly, ______.
A．so you'd better fertilize them
B．probably because the supply of nitrogen is cut off
C．simply because they can't absorb nitrogen from the soil
D．and then they will die slowly小题4:Which of the following is true?
A．Meat-eating plants look and act like other green plants.
B．It's hard to get nutrients in the soil when acidity is high.
C．The Venus' flytrap eats flies to get nutrient from them.
D．Green plants make sugar at night.
