When people want to know about the wcather, they usually go to there radios, TVs, pewspapers, or to the Internet. However, you can also find many weather signs among wildlife, because of their highly 题目和参考答案——青夏教育精英家教网—

题目内容

When people want to know about the wcather, they usually go to there radios, TVs, pewspapers, or to the Internet. However, you can also find many weather signs among wildlife, because of their highly developed senses. Drops in air pressure（压力） produce an effect on small animals in many ways. Mice and deer are good weather indicators. People who spend a lot of time outdoors have observed that, before a storm, field mice come out of their holes and run around, Deer leave high ground and come down from the mountains.

Birds are especially good weather indicators because they also show the effect of a prcssure drop in many ways. For example, some birds become irritable（急躁的）and qusrrelsome and will fight over a picce of bread. Other birds chirp（叽叽喳喳）and sing just before a storm. It seems they know they won’t get snother chance for an bour on two. Birds also seek safe placcs before a storm, You will sometimes see birds settling in trees or gathering together on a wire close to a building. Pre-storm low pressure makes the are so thin that birds have difficulty flying.

It is unusual to see many birds flying overhead in the summertime, rather than during the periods in the spring or autumn. Watch for other weather signs if you see this. If they fly in the wrong direction,they may be flying abead of a storm.

By paying closer attention to some important signs in nature, we can become better prepared for any kind of weather.

57．The word“indicators”in paragraph I probably means .

A．maps B．services C．signs D．stations

58．There will be a storm if birds .

A．make more noise than usual B．fly in different directions

C．come down from tall trees D．share a piece of bread

59．How can birds sense the coming of a storm?

A．By feeling a drop in air temperature.

B．By noticing the change of wind directions.

C．By feeling a drop in air pressure.

D．By notieing the movements of other animals.

60．The best title for the text would be .

A．Signs of a Storm B．Drops in Air Pressure

C．Animals’Sharp Senses D．Nature’s Weather Signs

CACD

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Can people change their skin colour without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin colour.

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However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebrafish genes.

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But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.

Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin colour, said Cheng.

The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin colour without damaging it like chemical treatment did on Michael Jackson.

The passage mainly tells us that ________.

A. people can not change their skin colour without any pain

B. the new discovery could lead to search into ways to change skin colour safely

C. pop king Michael Jackson often changed his skin colour as he liked

D. scientists have found out that people’s skin colour is determined by the gene

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A. nowadays people who want to change their skin colour have to suffer a lot from the damage caused by the chemical treatment

B. Europeans and Africans have the same gene

C. the new discovery could help to find medical treatments for skin cancer

D. there are two kinds of genes

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A. find the different genes of humans’

B. prove the humans’ skin colour is determined by the pigment gene

C. find out the reason why the Africans’ skin colour is dark

D. find out the ways of changing peopl’s skin colour

The writer’s attitude towards the discovery is ________.

A. neutral B. negative C. positive D. indifferent

Can people change their skin colour without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin colour.

It appears that, like the golden zebrafish, light-skinned Europeans also have a mutation(变异) in the gene for melanosome production. This results in less pigmented skin.

However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebrafish genes.

Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun(太阳光紫外线), which can cause skin cancer.But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin colour, said Cheng.

The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin colour without damaging it like chemical treatment did on Michael Jackson.

The passage mainly tells us that ________.

A. people can not change their skin colour without any pain

B. the new discovery could lead to search into ways to change skin colour safely

C. pop king Michael Jackson often changed his skin colour as he liked

D. scientists have found out that people’s skin colour is determined by the gene

It can be inferred from the passage that ________.

A. nowadays people who want to change their skin colour have to suffer a lot from the damage caused by the chemical treatment B. Europeans and Africans have the same gene

C. the new discovery could help to find medical treatments for skin cancer D. there are two kinds of genes

Scientists have done an experiment on a dark-striped zebra fish in order to ________.

A. find the different genes of humans’

B. prove the humans’ skin colour is determined by the pigment gene

C. find out the reason why the Africans’ skin colour is dark D. find out the ways of changing peopl’s skin colour

The reason why Europeans are light-skinned is probably that ________.

A. they are born light-skinned people

B. light-skinned Europeans have mutation in the gen for melanosome production

C. they have fewer activities outside D. they pay much attention to protecting their skin

The writer’s attitude towards the discovery is ________.

A. neutral B. negative C. positive D. indifferent

Can people change their skin colour without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin colour.

It appears that, like the golden zebrafish, light-skinned Europeans also have a mutation(变异) in the gene for melanosome production. This results in less pigmented skin.

However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebrafish genes.

Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun(太阳光紫外线), which can cause skin cancer.

But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.

Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin colour, said Cheng.

The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin colour without damaging it like chemical treatment did on Michael Jackson.

51. The passage mainly tells us that ________.

A. people can not change their skin colour without any pain

B. the new discovery could lead to search into ways to change skin colour safely

C. pop king Michael Jackson often changed his skin colour as he liked

D. scientists have found out that people’s skin colour is determined by the gene

52. It can be inferred from the passage that ________.

A. nowadays people who want to change their skin colour have to suffer a lot from the damage caused by the chemical treatment

B. Europeans and Africans have the same gene

C. the new discovery could help to find medical treatments for skin cancer

D. there are two kinds of genes

53. Scientists have done an experiment on a dark-striped zebra fish in order to ________.

A. find the different genes of humans’

B. prove the humans’ skin colour is determined by the pigment gene

C. find out the reason why the Africans’ skin colour is dark

D. find out the ways of changing peopl’s skin colour

54. The reason why Europeans are light-skinned is probably that ________.

A. they are born light-skinned people

B. light-skinned Europeans have mutation in the gen for melanosome production

C. they have fewer activities outside

D. they pay much attention to protecting their skin

55. The writer’s attitude towards the discovery is ________.

A. neutral B. negative C. positive D. indifferent

Can people change their skin colour without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin colour.

It appears that, like the golden zebrafish, light-skinned Europeans also have a mutation(变异) in the gene for melanosome production. This results in less pigmented skin.

However, Keith Cheng, leader of the research team, points out that the mutation is dif ferent in human and zebrafish genes.

Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun(太阳光紫外线), which can cause skin cancer.

But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vit amin D. So the related gene changes, according to Cheng.

Asians have the same version of the gene as Africans, so they pr obably acquired their light skin through the action of some other gene that affects skin colour, said Cheng.

The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin colour without damaging it like chemical treatment did on Michael Jackson.

1.. The passage mainly tells us that ________.

A. people can not change their skin colour without any pain

B. the new discovery could lead to search into ways to change skin colour safely

C. pop king Michael Jackson often changed his skin colour as he liked

D. scientists have found out that people’s skin colour is determined by the gene

2.. Scientists have done an experiment on a dark-striped zebra fish in order to ________.

A. find the different genes of humans’

B. prove the humans’ skin colour is determined by the pigment gene

C. find out the reason why the Africans’ skin colour is dark

D. find out the ways of changing peopl’s skin colour

3.. The reason why Europeans are light-skinned is probably that ________.

A. they are born light-skinned people