题目内容
Space travel is definitely bad for astronauts’ bones, reducing their bone density(密度) after only a month of weightlessness, according to French research published on Friday.
Laurence Vico and his fellow workers at St Etienne University called for more research into the effects of microgravity, after their study of 15 astronauts from the Russian MIR station showed bone loss continued throughout space flights.
“Bone loss was especially striking in four astronauts, ” the scientists reported in the Lancet Medical Journal.
They measured the bone mineral density (BMD) of bones in the forearm(前臂) and lower leg of the astronauts who had spent one to six months in space.
The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone, but barely changed in the radius(桡骨) of the forearm. “Our results indicate the need to investigate not only different bones, but also different areas of the same bone since not all sites of the skeleton (骨架) are similarly affected by space conditions, ” they added.
Without gravity the body isn’t bearing any weight so there is no need for calcium (钙) which makes bones strong, and it becomes empty into the bloodstream.
The research team suggested in future scientists should try to determine if the loss of bone density was only on weight-bearing bones on longer flights, also the possible recovery after returning to Earth.
French scientists did their research on Russian astronauts, because _______.
A. they only cared for the Russian astronauts
B. they were not interested in their own astronauts
C. the Russian government invited them to do their research
D. the Russian astronauts worked in space for a long time
Scientists have found that _______.
A. the BMD loss may cause serious illness to astronauts
B. the BMD loss may cause some change in astronauts’ bodies
C. astronauts shouldn’t care about the BMD loss
D. astronauts should take some calcium before space travel
What cause the BMD loss to astronauts, according to this passage?
A. The food they eat in space. B. The drinks they take in space.
C. The temperature in space. D. The gravity in space.
In the third paragraph, the word “striking” means ______.
A. unusual B. simple C. weak D. slow
【小题1】D
【小题2】B
【小题3】D
【小题4】A
解析:
本文介绍了法国对太空宇航员长期在太空飞行,会使骨里的密度减少而对骨不利的研究。
【小题1】细节题。根据文章第4段的定语从句who had spent one to six months in space可推知此题答案为D。
【小题2】细节题。根据文章第5段第1句The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone可推知此题答案为B。
【小题3】细节题。根据文章第6段Without gravity…所引起的结果,可推知此题答案为D。
【小题4】词义猜测题。上文提到对十五人进行研究表明在整个航行过程中骨损在继续,下文再说especially striking,可知是“特别明显”的事,因此选A。
It comes as ______ surprise that ______ dream of space travel will soon come true.
A.a; the | B.the; the | C.the; a | D.a; 不填 |
Alaskan black bears hibernate for up to seven months a year, during which time they do not eat or drink, before waking up in virtually the same physical state they fell asleep in.
Now experts hope to develop methods of putting humans into a similar state which could help astronauts survive long missions and lead to new ways of treating severely ill patients.
While many studies have examined hibernation in mice and hedgehogs, little research has been done into the same condition in larger mammals such as bears.
But new research conducted at the Institute of Arctic Biology at the University of Alaska monitored the animals' body temperature, heart rate and muscle movements while they slept.
The research results showed that during a five-month hibernation the bears’ body temeratures varied between 30℃ and 36℃ in cycles that lasted between two and seven days—a pattern that was previously unknown in hibernating animals.
The research project leader said, "If our research could help by showing how to reduce metabolic(新陈代谢的) rates and oxygen demands in human tissues, one could possibly save severely ill patients. We simply need to know how to turn things on and off to take advantage of the different levels of hibernation."
Craig Heller, of Stanford University, who contributed to the study, added: "There has always been a thought that, if there is ever long-distance space travel, it would be good to be able to put people into a state of lower metabolism or a state of hibernation. That's almost science fiction but you can see the logical basis."
【小题1】We know from the text that .
A.during winter Alaskan black bears sleep for more than half a year |
B.researchers have examined hibernation in humans |
C.experts have got no results from their research |
D.Craig Heller is a leader from the Institute of Arctic Biology |
.
A.The Latest Research Results |
B.New Methods of Putting Humans into Hibernation |
C.Alaskan Black Bears Hibernate |
D.Astronauts Could Hibernate Like Bears |
A.many studies have examined hibernation in mice and bears as well |
B.humans' body temperatures vary between 30℃ and 36℃ while they sleep |
C.research into hibernation in animals may help deadly patients stay longer |
D.scientists have already take advantage of the different levels of hibernation in space missions |