首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
医学
Scientists used to believe adult brains did not grow any new neurons, but it has emerged that new neurons can sprout in the brai
Scientists used to believe adult brains did not grow any new neurons, but it has emerged that new neurons can sprout in the brai
admin
2013-11-14
61
问题
Scientists used to believe adult brains did not grow any new neurons, but it has emerged that new neurons can sprout in the brains of adult rats, birds and even humans. Understanding the process could be important, for finding ways to treat diseases such as Alzheimer’s in which neurons are destroyed.
Most neurons sprouting in adulthood seem to be in the hippocampus, a structure involved in learning and memory. But they rarely survive more than a few weeks. "We thought they were possibly dying because they were deprived of some sort of input," says Elizabeth Gould, a neuroscientist at Princeton. Because of the location, Gould and her colleagues suspect that learning itself might bolster the new neurons’ survival, and that only tasks involving the hippocampus would do the trick.
To test this, they injected adult male rats with a substance that labeled newborn neurons so that they could be tracked. Later, they gave some of the rats standard tasks. One involved using visual and spatial cues, such as posters on a well, to learn to find a platform hidden under murky water. In another, the rats learnt to associate a noise with a tiny shock half a second later. Both these tasks use the hippocampus — if this structure is damaged, rats can’t do them.
Meanwhile, the researchers gave other rats similar tasks that did not require the hippocampus finding a platform that was easily visible in water, for instance. Other members of the control group simply paddled in a tub of water or listened to noises.
The team reported in Nature Neuroscience that the animals given the tasks that activate the hippocampus kept twice as many of their new neurons alive as the others. "Learning opportunities increase the number of neurons," says Gould.
But Fred Gage and his colleagues at the Salk Institute for Biological Studies in La Jolla, California, dispute this. In the same issue of Nature Neuroscience, they reported that similar water maze experiments on mice did not help new neurons survive.
Gould thinks the difference arose because the groups labeled new neurons at different times. She gave the animals tasks two weeks after the neurons were labeled. When the new cells would normally be dying, she thinks the Salk group put their mice to work too early for new neurons to benefit. "By the time the cells were degenerating, the animals were not learning anything." she says.
Which of the following can clearly tell the two groups of rats from each other in the test?
选项
A、The water used.
B、The noises played.
C、The neurons newly born.
D、The hippocampus involved.
答案
D
解析
题干:在测试中,下列哪一个能清晰地将两组老鼠辨别开来?此题为细节定位题,原文中的第四段第一句话可以得出答案。
转载请注明原文地址:https://www.kaotiyun.com/show/DJU3777K
本试题收录于:
医学博士外语题库考研分类
0
医学博士外语
考研
相关试题推荐
Severalclassesofbittercitruscompoundhavelookedpromisingasanticanceragentsinlaboratorytests.Anewstudyindicates
Imagineadiseasespreadingacrosstheglobe,killingmostlymiddle-agedpeopleorleavingthemchronicallydisabled.Thenoned
Cultureshockmightbecalledanoccupationaldiseaseofpeoplewhohavebeensuddenlytransplantedabroad.Likemostailments,
Cultureshockmightbecalledanoccupationaldiseaseofpeoplewhohavebeensuddenlytransplantedabroad.Likemostailments,
Cultureshockmightbecalledanoccupationaldiseaseofpeoplewhohavebeensuddenlytransplantedabroad.Likemostailments,
Cultureshockmightbecalledanoccupationaldiseaseofpeoplewhohavebeensuddenlytransplantedabroad.Likemostailments,
Youfeelgenerallydepressedandunabletoconcentrate.Your【C1】______ofdailyactivitymaychange;youfindyourself【C2】______a
Youfeelgenerallydepressedandunabletoconcentrate.Your【C1】______ofdailyactivitymaychange;youfindyourself【C2】______a
Youfeelgenerallydepressedandunabletoconcentrate.Your【C1】______ofdailyactivitymaychange;youfindyourself【C2】______a
Twoequallybrilliantscientistsapplyforaprestigiousresearchfellowshipawardedbyatopscientificorganization.Oneiswh
随机试题
干姜治咳喘的机理是
《耕地占补平衡考核办法》规定,县级以上地方农业部门负责本行政区域内耕地占补平衡的考核工作。()。
根据《企业财务会计报告条例》的规定,企业对外提供虚假财务会计报告,可以对企业()。
将建筑物垂直地面的各种墙面,进行( )而得到的投影图称为立面图。
下列情况中,符合银行发放个人贷款要求的是()。
根据《人民币银行结算账户管理办法》的规定,下列款项中,可以转入个人银行结算账户的有()。
给定资料1.2013年11月10日22点,杭州华星时代大厦,天猫“双十一”购物节主战场,灯火通明。据悉,11月11日当天,阿里组建了5000人团队加班加点保障“双十一”顺利进行。为了防止意外,阿里这次为了天猫“11.11”购物狂欢节在各
若x,y均为正整数,则方程15×22+1=y2的正整数解(x,y)的个数是
使用文件系统时,通常要显式地进行open()操作,这样做的目的是()。
ArecentstudybytheCenterforEconomicPolicyResearchsaysthat,inordertoeaseimbalances,theEuropeanUnionneedstoma
最新回复
(
0
)