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  3. 共用题干 第二篇Night of the Living AntsWhen an

共用题干 第二篇Night of the Living AntsWhen an

资格题库2022-08-02  38
问题 共用题干第二篇

Night of the Living Ants

When an ant dies,other ants move the dead insect out of the nest.This behavior is interesting to scien-
tists,who wonder how ants know for sure一and so soon一that another ant is dead.
Dong-Hwan Choe,a scientist at the University of California,found that Argentine ants have a chemical
on the outside of their bodies that signals to other ants,"I'm dead一take me away."
But there's a twist to Choe's discovery. These ants behave a little bit like zombies（僵尸）.Choe says
that the living ants一not just the dead ones一have this death chemicals. In other words,while an ant crawls
around,perhaps in a picnic or home,it's telling other ants that it's dead.
What keeps ants from hauling away the living dead? Choe found that Argentine ants have two additional
chemicals on their bodies,and these tell nearby ants something like,"Wait一I'm not dead yet."So Choe's
research turned up two sets of chemical signals in ants:one says,"I'm dead,"the other set says,"I'm not
dead yet."
Other scientists have tried to figure out how ants know when another ant is dead.If an ant is knocked
unconscious,other ants leave it alone until it wakes up.That means ants know that unmoving ants can still be
alive.
Choe suspects that when an Argentine ant dies,the chemical that says"Wait一I'm not dead yet"quickly
goes away. Once that chemical is gone,only the one that says"I'm dead"is left."It's because the dead ant
no longer smells like a living ant that it gets carried to the graveyard（墓地）,not because its body releases
new,unique chemicals after death,"said Choe.When other ants detect the"dead"chemical without the"not
dead yet" chemical,they haul away the body. This was Choe's hypothesis（假设）.
To test his hypothesis,Choe and his team put different chemicals on Argentine ant pupae（蛹）.When
the scientists used the"I'm dead"chemical,other ants quickly hauled the treated pupae away.When the sci-
entists used the"Wait一I'm not dead yet"chemical,other ants left the treated pupae alone.Choe believes
this behavior shows that the" not dead yet" chemical overrides（优先于）the" dead" chemical when picked up
by adult ants.And that when an ant dies,the"not dead yet"chemical fades away.Other nearby ants then de-
tect the remaining"dead"chemical and remove the body from the nest.What is meant by"death chemical"mentioned in Paragraph 3?A:A chemical that contains poison.B:A chemical that causes death.C:A chemical that announces death.D:A chemical that prevents death.
选项 What is meant by"death chemical"mentioned in Paragraph 3?
A:A chemical that contains poison.
B:A chemical that causes death.
C:A chemical that announces death.
D:A chemical that prevents death.
答案 C
解析 第二段提到：加州大学的科学家周东环发现阿根廷蚂蚁的身体能向外释放一种化学物 质来告诉同伴：“我死了，把我挪走吧。”
根据第五段第二句可推断出C项错误。
倒数第二段提到：一只阿根廷蚂蚁死后，发出“等等，我还没死呢”这一信号的化学物质 立刻消失，因此选D。
周的假设是表明“我死了”的化学物质是蚂蚁本身就有的，而非死后释放的。它和表明 “我没死”的化学物质同时存在于活着的蚂蚁身上，只不过其优先权不如表明“我没死”的化学 物质。实验结果是：当科学家用“我已死”化学物质时，蚂蚁们立刻将处理过的蛹拉走。当科 学家使用“等等，我还没死”化学物质时，其他蚂蚁并不碰这个蛹。所以，周的假设是正确的。
本文主要讲述了蚂蚁们如何迅速准确地得知同伴死了，所以选D。 第三篇 本文介绍了在山口发现的一具躺在冰上的尸体，以及由此引发的研究和种种猜测。
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