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You've probably learned that bears eat a lot before hibernating （冬眠），putting on weight suddenly.It's an enviable practice，because those bears don't have the same health problems as fat people.A study published in Cell Reports has found that it might be due to the bear's friendly gut microbes （腸道細(xì)菌）.
   In summer，bears go through an extreme period of eating，while they eat nothing about six months during winter hibernation.To compare the microbiomes （微生物） of both seasons，the researchers collected the samples of their waste from 16 wild bears during hibernation and in summer.What they found is that the bear's lifestyle changes dramatically with seasons.During hibernation，the kinds of microbiomes became less than the summer samples.
   To find out how that might affect metabolism （新陳代謝），the researchers transferred the microbes from the winter and the summer into lab mice.Mice with the summer microbes gained more weight than those with the winter microbes.However，those fatter summer mice weren't different from the winter mice in their glucose （葡萄糖） metabolism. "Thus，the bear may be atypical model for healthy obesity （肥胖） and studying hibernation might be a promising approach to developing new treatments for obesity，" the authors write.
   However，there are still more researches needed before humans benefit from bear gut microbes.The researchers note that relying on free-ranging wild bears means they know little about their food intake and other habits.And though they were able to produce interesting metabolic results in mice，mice are quite different from humans.And another research suggests that exposure to cold can also change the composition of gut bacteria，improving glucose metabolism and fat burning abilities in mice.

（1）Why don't bears suffer the same health problems as fat people？
D
D

A．Because of hibernation.
B．Because of no exercise.
C．Because of their special food intake.
D．Because of some friendly gut microbes.
（2）What can we learn from the text？
B
B

A．Bears' weight increases quickly during hibernating.
B．Bears' lifestyle changes greatly in different seasons.
C．Bears' microbiomes in summer are less than those in winter.
D．Bears' glucose metabolism varies with seasons.
（3）What's the author's attitude to the benefits of the research for human？
C
C

A．Favorable.
B．Disapproving.
C．Cautious.
D．Curious.
（4）What is the passage mainly about？
D
D

A．The way of bears' metabolism.
B．The seasonal lifestyles of bears.
C．The approach to treating obesity.
D．The cause of bears' healthy obesity.

【考點】科普知識；說明文．
【答案】D；B；C；D
【解答】
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發(fā)布：2024/5/23 20:38:36組卷：14引用：1難度：0.5
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    發(fā)布：2024/11/9 9:0:1組卷：7引用：1難度：0.6

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    發(fā)布：2024/10/25 17:0:1組卷：1引用：1難度：0.3

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    發(fā)布：2024/10/19 0:0:1組卷：13引用：2難度：0.5
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