【題目】After losing contact for twenty years, they met again _________ in a party.
A.by mistake B.by coincidence
C.on purpose D.on display
科目:高中英語 來源: 題型:
【題目】【原創(chuàng)】Humans are well-equipped for life on Earth. But in space, it is different. Low or zero gravity changes how the blood flows and causes motion sickness, muscle loss and tiredness. Weightlessness can also cause bone loss. But scientists are experimenting with little worms to better understand how space travel affects astronauts.
The millimeter-long worm is called C. elegans. The see-through worm is often used in medical studies because its life is only about two weeks long. Seventy percent of its DNA is the same as human DNA.
Sabanayagam is a scientist, who built a micro-gravity simulator to test how C. elegans would perform in the actual zero gravity of space.
Scientists put the worms into the simiulator full of water. After a week they take out the worms. They look for changes in the worms' epigenome,which are chemical markers that tell the DNA in the cells how to perform. The epigenome can be changed by the environment. And those changes pass from one generation of worms to the next.
"When the worms are in a liquid environment, some epigenomic marks remain even when we take the animal out of the liquid environment and put it back into normal ground conditions. So its offspring keeps this epigenomic memory of the parents' liquid environment or microgravity environment."
The information the scientists have gathered suggests that the epigenomic marks appear during the early part of a worm’s life.
Mr. Sabanayagam says he thinks scientists can find genes in the human similar to those in the worms that responded to microgravity and scientists could possibly observe those genes closely when astronauts travel in space.
Sabanayagam expects C. elegans to visit the International Space Station within two years. He says he hopes information gathered from the worm studies can be used to develop simple, low-cost and quick tests to measure an astronaut's health.
【1】What does the underlined word” zero gravity” mean?
A. Seasickness B. Muscle loss
C. Weightlessness D. Tiredness.
【2】 From the passage we can know C. elegans _____.
A. has exactly the same DNA as human
B. is harmful to human
C. is often used in agricultural research
D. has a short life period
【3】Why do scientists experiment with C. elegans?
A. Because it has strong life power in water.
B. Because they want to find how space travel affects astronauts
C. Because the worm will be taken into space.
D. Because they want to find what its DNA like.
【4】What is Sabanayagam’s attitude toward the result of the experiment?
A. Hopeful and satisfied.
B. Doubtful and unsure.
C. Sad and disappointed.
D. Surprised and unbelievable.
【5】Which section of a newspaper can you find the passage?
A. Education. B. Science.
C. Advertisement. D. Entertainment.
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【題目】Undoubtedly, life teaches us not to regret over yesterday, for it has passed and is __________ our control.
A. against B. beyond
C. in D. on
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【題目】There was __________ apples in the basket and there __________ quantities of milk in the bucket.
A. a number of; were B. quantities of; was
C. a quantity of; were D. a good many; was
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【題目】No matter how frustrated she was in her heart, she would _______ others with a smile as usual; she didn’t want to let them know.
A.inspire B.serve C.help D.treat
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【題目】If you drive from the airport, go on the motorway and follow the __________.
A. signs B. ways
C. point D. design
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【題目】Sichuan is located __________ the west of China while Japan lies __________ the east of China.
A. to; to B. in; in
C. in; to D. to; in
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【題目】__________ the numbers in employment, the hotel industry was the second largest industry in this country last year.
A. In spite of B. In case of
C. In terms of D. In praise of
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【題目】Shanghai is an industrial city, located __________ the east coast of China.
A. to B.on
C. off D. in
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