GRE

GREGRE阅读阅读真题文章

GRE阅读真题考前突击训练1

2018年04月24日 10:50:13来源:GRE考试网
导读:今天的GRE阅读练习已经准备好了,考生们也快速调整状态进入做题模拟式吧!今天分享的题目可都是历年的真题哦,可是很有含金量的!多做真题有助于我们了解出题者意图,同时也是对考试复习很有帮助的。

>>GRE考试阅读真题练习:GRE阅读真题考前突击训练1

>>GRE考试精品课程训练

In laboratories, healthy adult human brain neurons typically live no more than a few hours, making extensive research impossible. Furthermore, scientists' inability to reproduce healthy neurons has prevented the use of neurons in experimental treatments of severe neurological disorders.

However, two researchers at the Johns Hopkins University School of Medicine have successfully maintained mature, human brain neurons in long-term cultures by using cells obtained during surgery on an 18-month-old victim of unilateral megalencephaly. The rare disorder, in which one side of the brain grows substantially larger than the other, occurs when neurons in the abnormal hemisphere undergo too many cell divisions before they mature. The neuronal imbalance in the brain of the infant caused seizures, prompting surgeons to remove the enlarged hemisphere---a treatment that has proven successful in similar cases. The researchers then took neurons from the excised brain matter and placed them in a blood-rich culture medium. After days, many of the cells had died, but a few continued to grow and divide. Nineteen months later, the team had subcultured colonies of neurons onto new culture plates more than 20 times, with no significant changes in cellular appearance or growth characteristics.

Scientists still don't know what triggers the proliferation of neurons in unilateral megalencephaly. The neurons cultivated at Johns Hopkins---unlike those culled from tumors are not cancerous, and accordingly are much more valuable as research tools. Finally, the experiment presents the possibility that such neurons could be used in experimental treatments that currently use fetal brain cells, sidestepping an uncomfortable ethical issue.

Which sentence in the second paragraph, in which the author makes a conclusion, is not supported with any factual or anecdotal evidence?

A.will allow researchers to expand their knowledge of neurological workings

B.is necessary to cure unilateral megalencephaly

C.is a viable medical procedure in some cases

D.is usually performed on infants who suffer from unilateral megalencephaly

E.is a rare procedure that is performed as a last resort

The passage supplies information to answer which of the following questions?

A.How old is the average unilateral megalencephaly patient?

B.Can fetal brain cells be used to treat unilateral megalencephaly?

C.Have scientists found a way to allow cells from victims of unilateral megalencephaly to exist outside of the body?

D.How long can neurons culled from tumors be sustained outside the body?

E.Will scientists find further experimental uses for neurons culled from unilateral megalencephaly victims?

In the second paragraph, select the sentence in which a term is introduced that requires elucidation in a later sentence.

1.正确的答案:C

2.正确的答案:C

3.正确的答案:However, two researchers at the Johns Hopkins University School of Medicine have successfully maintained mature, human brain neurons in long-term cultures by using cells obtained during surgery on an 18-month-old victim of unilateral megalencephaly.

上面的真题大家都会做了吗,登录坦途网GRE考试频道可以找到更多的真题哦,也能了解更多关于GRE考试的知识点,大家考试加油吧!

温馨提示:因考试政策、内容不断变化与调整,坦途网提供的以上信息仅供参考,如有异议,请考生以权威部门公布的内容为准!

GRE培训课程免费试听

预约免费体验课

教育顾问会第一时间安排您的体验课!

课程预约立即提交
最新文章
电话咨询在线咨询资料领取