A
Plants are living things. So can they feel pain? Plants don't feel pain the same way animals and people do, says Anke Steppuhn. She is a scientist at the Free University of Berlin in Germany." What we define as pain usually has to do with a nervous system," Steppuhn explains, When you put your hand too close a hot stove, nerve cells send a signal to your rain. Your brain decodes(解码)that signal as pain. This causes you pull your hand away before any serious damage is done.
Plants don't have nerves or brains, so they can't fenl pain like we do." But plants do recognize when something is hurting them," Steppuhn says. Because they are rooted to the ground, they can t escape a dangerous situation. So they need other ways of fighting back.
The biggest threat to a plant's life is getting eaten Some plants grow sharp little hairs. Other plants produce bad-tasting or even harmful chemicals. These for an attacker to abandon its meal. A plant called bittersweet nightshade does something even smarter, Steppuhn found When a slug(蛞蝓)chews holes in a nightshade's leaf, liquid begins dripping(滴下)around the wound. It is almost as if the plant were bleeding. The liquid is sugary nectar, and it happens to be a favorite food of ants. In their effort to collect the nectar, the ants swarm(蜂拥而至)all over the injured plant. They will attack anything that stands in their way. That includes the slug that damaged the plant in the first place. It's a very clever trick. Whenever a slug attacks a plant, the plant calls an army of ants to kill the slug.
Nectar isn't the only way plants attract bodyguards. They also release certain chemicals into the air when they are being eaten. People usually can't detect these smells. But wasps(黄蜂)can. When a wasp detects this cry for help, it races to the scene of the crime. If it finds the right kind of insect chewing down on the plant, the wasp will interrupt the attacker's meal. It will do this by laying eggs inside the insect's body!
1.Why do plants feel pain differently from us?
A. They don't know whether they're hurt.
B. They face different kinds of danger.
C. They don't have nervous systems.
D. They have slow response to pain.
2.What does the u
nderlined part"They”in Paragraph 3 refer to?
A. Ants B. Slugs C.Plants. D.Wasps.
3.Why do some plants need wasps?
A. To help them call bodyguards.
B. To keep them safe from attackers.
C. To let wasps lay eggs on their leaves.
D. To let their smells spread into the air.
4.What is the text mainly about?
A. How plants feel pain.
B. How plants attract insects.
C. How plants defend themselves.
D. How plants attack small animals.
答案 1-4 CABC
Plants are living things. So can they feel pain? Plants don't feel pain the same way animals and people do, says Anke Steppuhn. She is a scientist at the Free University of Berlin in Germany." What we define as pain usually has to do with a nervous system," Steppuhn explains, When you put your hand too close a hot stove, nerve cells send a signal to your rain. Your brain decodes(解码)that signal as pain. This causes you pull your hand away before any serious damage is done.
Plants don't have nerves or brains, so they can't fenl pain like we do." But plants do recognize when something is hurting them," Steppuhn says. Because they are rooted to the ground, they can t escape a dangerous situation. So they need other ways of fighting back.
The biggest threat to a plant's life is getting eaten Some plants grow sharp little hairs. Other plants produce bad-tasting or even harmful chemicals. These for an attacker to abandon its meal. A plant called bittersweet nightshade does something even smarter, Steppuhn found When a slug(蛞蝓)chews holes in a nightshade's leaf, liquid begins dripping(滴下)around the wound. It is almost as if the plant were bleeding. The liquid is sugary nectar, and it happens to be a favorite food of ants. In their effort to collect the nectar, the ants swarm(蜂拥而至)all over the injured plant. They will attack anything that stands in their way. That includes the slug that damaged the plant in the first place. It's a very clever trick. Whenever a slug attacks a plant, the plant calls an army of ants to kill the slug.
Nectar isn't the only way plants attract bodyguards. They also release certain chemicals into the air when they are being eaten. People usually can't detect these smells. But wasps(黄蜂)can. When a wasp detects this cry for help, it races to the scene of the crime. If it finds the right kind of insect chewing down on the plant, the wasp will interrupt the attacker's meal. It will do this by laying eggs inside the insect's body!
1.Why do plants feel pain differently from us?
A. They don't know whether they're hurt.
B. They face different kinds of danger.
C. They don't have nervous systems.
D. They have slow response to pain.
2.What does the u
nderlined part"They”in Paragraph 3 refer to?A. Ants B. Slugs C.Plants. D.Wasps.
3.Why do some plants need wasps?
A. To help them call bodyguards.
B. To keep them safe from attackers.
C. To let wasps lay eggs on their leaves.
D. To let their smells spread into the air.
4.What is the text mainly about?
A. How plants feel pain.
B. How plants attract insects.
C. How plants defend themselves.
D. How plants attack small animals.
答案 1-4 CABC
