Question

When an ant dies, other ants move the dead insect out. Sometimes, the dead ant get moved away very soon—within an hour of dying. This behavior is interesting to scientists, who wonder how ants know for sure—and so soon—that another ant is dead.

One scientist recently came up with a way to explain this ant behavior. Dong-Hwan Choe is a biologist. Choe found that Argentine ants have a chemical on the outside of their bodies that signals to other ants, “I’m dead—take me away.”

But there’s a twist to Choe’s discovery. Choe says that the living ants—not just the dead ones—have this death chemical. 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 dragging away the living ants？Choe found that Argentine ants have two additional chemicals on their bodies, and these tell nearby ants something like, “Wait—I’m not dead yet.” So Choe’s research turned up two sets of chemical signals in ants: one says, “I’m dead,” and 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, for example, 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-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, not because its body releases(釋放) new unique chemicals after death,” said Choe. When other ants detect the “dead” chemical without the “not dead yet” chemical, they drag away the body.

Understanding this behavior may help scientists figure out how to stop Argentine ants from invading new places and causing problems. Choe would like to find a way to use the newly discovered chemicals to spread ant killer to Argentine ant nests.

The ants’ removal behavior is important to the overall health of the nest. “Being able to quickly remove dead individuals and other possible sources of disease is extremely important to all animals living in societies, including us,” says Choe. “Think about all the effort and money that we invest daily in waste management.”

1.The underlined word “twist” in Paragraph 3 means             .

A．a(chǎn)n unexpected change                   B．a(chǎn) clear mistake

C．a(chǎn)n important key                        D．a(chǎn) shocking conclusion

2.Ants judge whether another one is dead or not depending on            .

A．the sense of taste                       B．the sense of smell

C．the sense of touch                      D．the sense of sight

3.The result of the research can be used to            .

A．kill troublesome pests

B．solve the problem of endangered species

C．prevent further expansion of the ants’ territory

D．keep the balance of nature

4.Why is it important to remove dead individuals?

A．Because it is easier to manage the living.

B．Because it can save money to deal with the waste.

C．Because it can provide more space for the living.

D．Because it can keep the living from suffering disease.

5.What might be the best title of the text?

A．Dead or living? It is easy to judge

B．Pulling away the dead ants is a difficult task

C．Ant nests have great undertaking capacity

D．Leaving it alone or taking it away? Ants feel puzzled

 

Answer 1

【答案】

1.A

2.B

3.C

4.D

5.A

【解析】

試題分析：本文介紹的是對螞蟻死了還是活著的判斷，介紹了螞蟻的、發(fā)出化學(xué)物質(zhì)的氣味來告訴人們具體的信息。

1.A 推理題。根據(jù)本句But there’s a twist to Choe’s discovery. Choe says that the living ants—not just the dead ones—have this death chemical.說明這里的twust是指和以前不一樣，因為活的螞蟻不僅僅那些死的螞蟻都有這樣的化學(xué)物質(zhì)。故這里的twist是指沒有預(yù)料到的改變，故A正確。

2.B 細節(jié)題。根據(jù)第二段2，3行Choe found that Argentine ants have a chemical on the outside of their bodies that signals to other ants, “I’m dead—take me away.說明螞蟻的身上有這樣的化學(xué)物質(zhì)，發(fā)出了這樣的氣味，故B正確。

3.C 推理題。根據(jù)文章最后一段前3行Understanding this behavior may help scientists figure out how to stop Argentine ants from invading new places and causing problems. Choe would like to find a way to use the newly discovered chemicals to spread ant killer to Argentine ant nests.說明這樣的研究結(jié)果會幫助人們阻止螞蟻的擴張，故C正確。

4.D 細節(jié)題。根據(jù)文章倒數(shù)2,3行“Being able to quickly remove dead individuals and other possible sources of disease is extremely important to all animals living in societies,說明D正確。

5.A 主旨大意題。本文介紹的是對螞蟻死了還是活著的判斷，介紹了螞蟻的、發(fā)出化學(xué)物質(zhì)的氣味來告訴人們具體的信息。故A正確。

考點：考查科普類短文閱讀

點評：此類文章的最大的障礙是詞匯以及考生對閱讀內(nèi)容的不熟悉，需要考生在閱讀的時候有足夠的耐心。要養(yǎng)成在上下文串聯(lián)中猜測詞義的能力，根據(jù)上下文中出現(xiàn)的同義詞，近義詞，反義詞，以及詞義的解釋來理解生詞。同時要抓住文章的中心，不要受其他信息的影響。要根據(jù)題目及選項以及文章的上下文串聯(lián)合理的判斷推理。