2015年武汉大学考博英语真题5

考博英语责任编辑：王觅 2019-01-23

摘要：希赛网英语考试频道为大家分享“2015年武汉大学考博英语真题5（阅读理解）”，更多考博英语相关信息，请关注希赛网英语考试频道。

希赛网英语考试频道为大家分享“2015年武汉大学考博英语真题5（阅读理解）”，更多考博英语相关信息，请关注希赛网英语考试频道。

Passage Five

Any hope of a fountain of youth to stop people from getting older is a long way off, with science just beginning to understand the complex genetic, physical and hormonal causes of aging. But experts said there were interesting targets for study, including genes involved in Alzheimer’s disease, the hormone DHEA and the role of exercises in keeping people young.

Steven Lamberts and colleagues noted that levels of DHEA were much lower in older people. One study in adults showed taking DHEA tablets “ induced a remarkable increase in perceived physical and physiological wellbeing in both men and women without having an effect on sex”. Other studies on rats showed giving them DHEA could prevent obesity and diabetes. But they said much more study was needed.

Cable Finch and Rudoph Tanzi said it was conceivable that genetic engineering experiments could transfer genes from one species to another to alter life span. However, it seems unlikely that a few genes determine the 25 fold difference in life spans between rats and humans. An instructive example is the 10-fold difference in lifespans of female worker bees and queens of the same genotype, which show much slower aging during lifespans of many active years of egg production. The difference一what the bees were fed as juveniles.

One interesting genetic candidate was the APOE gene, mutations of which are linked with Alzheimer’s disease. One version of this gene does seem to be linked with long life, although many more studies are needed.

For those who do not want to wait, Lamberts’ team said exercise can be key to preventing the frailty that aging brings. Loss of muscle strength is an important factor in the process of frailty. One study in home for the elderly showed a sedentary lifestyle greatly contributes to this. Supervised resistance exercise training could double muscle strength and significantly increase gait velocity and stair- climbing power. This demonstrates that frailty in the elderly is not an irreversible effect of aging and disease and can be reduced and perhaps even prevented.

17. The specific purpose of setting Alzheimer’s disease as the research target is to .

A. discover a way to decode all the human genes

B. find out something about the genetic cause of aging

C. locate the fountain of youth in human bodies

D. probe into the role of exercise in retaining youth

18. The second paragraph implies that taking DHEA tablets would .

A. certainly make people younger

B. help you lose some weight

C. promote no increase in sex drive

D. show little health effect like greater body strength

19. In the example cited by Finch and Tanzi, lifespan was most likely affected by •

A. transferring certain genes B. different strains between species