If an insect goes for a drink and gets wet, what will happen..

第1题

Night of the Living Ants When an ant dies，other ants move the dead insect out of the nest．

Night of the Living Ants

When an ant dies，other ants move the dead insect out of the nest．This behavior. is interesting to scientists，who wonder how ants know for sure-and so soon-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-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 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-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-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 scientists used the“Wait-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(优胜于)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 detect the remaining“dead”chemical and remove the body from the nest．

The phrase“this death chemical”in paragraph 3 refers to

A．the chemical that contains poison．

B．the chemical that announces death．

C．the chemical that prevents death．

D．the chemical that causes death．

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第2题

听力原文：Welcome to Everglade National Park. The Everglade is a watery plain covered with

听力原文： Welcome to Everglade National Park. The Everglade is a watery plain covered with saw grass that's home to numerous species of plants and wild life. And one and a half million acre is too big to see it all today, but this tour will offer you a good sampling. Our tour bus will stop first at Tailor Slue. This is a good place to start because it is home to many plants and animals typically associated with The Everglade. You will see many exotic birds and of course the world famous alligators. Don't worry there's a border walk that goes across the marsh so yon can look down at the animals in the water from a safe distance. The border walk is high enough to give you a great view of saw grass quarry. From there we'll head for some other marshy and even jungle-like areas that feature wonderful tropical plant life. For those of you who'd like a closer view of saw grass quarry, you might consider running a canoe sometime during your visit here. However don't do this unless you have a very good sense of direction and can negotiate your way through all grass. We hate to have to come looking for you. You have a good fortune of being here in winter, the best time of the year to visit. During the spring and summer, the mosquitoes were just about to eat you 'alive. Right now they are not so bothersome but you will still want to use insect repellent.

(30)

A．To inform. visitors of the park's history.

B．To provide an overview of the park's main attractions.

C．To show visitors remote places in the park.

D．To teach visitors how to photograph wildlife best.

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第3题

SECTION BPASSAGESDirections: In this section, you will hear several passages. Listen to th

SECTION B PASSAGES

Directions: In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow.

听力原文： Welcome to Everglade's National Park. The Everglade is a watery plain covered with saw-grass that's the home to numerous species of plants and wild life. And one and half million acres is too big to see it all today. But this tout will offer you a good sampling. Our tour bus will stop first at Tailor Slue. This is a good place to start because it is home to many of the plants and animals typically associated with the everglade. You'll see many exotic birds and of course a world famous alligators. Don't worry. There's a boardwalk that goes across the marsh, so you can look down at the animals in the water from a safe distance. The boardwalk is high enough to give you a great view of the saw grass prairie. From there we'll head at some other marshy and even jungle—like areas that feature wonderful tropical plant life. For those of you who'd like a close view of the saw grass prairie, you might consider running a canoe sometime during your visit here. However, don't do this unless you have a very good sense of direction and can negotiate your way through tall grass. We hate to have to come looking for you. You have a good fortune of being here in the winter, the best time of the year to visit. During the spring and summer the mosquitoes will just about to eat you alive. Right now, they are not so bothersome, but you'll soon want to use an insect repellent.

What is the main purpose of the tour？

A．To inform. visitors of the park's history.

B．To provide an overview of the park's main attractions.

C．To show visitors remote places in the park.

D．To teach visitors how best to photograph wildlife.

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第4题

Night of the Living Ants When an ant dies，other ants move the dead insect out of the nest．

Night of the Living Ants

When an ant dies，other ants move the dead insect out of the nest．This behavior. is interesting to scientists，who wonder how ants know for sure-and so soon-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-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 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-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-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 scientists used the“Wait-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(优胜于)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 detect the remaining“dead”chemical and remove the body from the nest．

The phrase“this death chemical”in paragraph 3 refers to

A．the chemical that contains poison．

B．the chemical that announces death．

C．the chemical that prevents death．

D．the chemical that causes death．

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第5题

insect infestation

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第6题

insect（）

A.昆虫