阅读理解（第3l～45题，每题3分，共15分）
请根据短文内容，为每题确定1个最佳选项。
Walking to Exercise the Brain
Do you think sitting and studying all the time will improve your grades?Think again．Getting some exercise may help，too．
New research with older people suggests that taking regular walks helps them pay attention better than if they didn't exercise．
Previous research had shown that mice learn，remember，and pay attention better after a few weeks of working out on a running wheel．Mice that exercise have greater blood flow to the brain than those who don't．Their brain cells also make more connections．
Neuroscientists from the University at Urbana-Champaign wanted to find out if the same thing is true for people．First，they measured the physical fitness of 41 adults，ages 58 to 77，after each per-son walked 1 mile．Then，participants looked at arrows on a computer sczeen and had to use com-puter keys to show which way one particular arrow was pointing．
Adults who were physically fit were faster at the arrow task，and their answers were just as ac- curate as their less-fit peers,the researchers found．The fitter participants also had more blood flow to a part of their brain responsible for paying attention and making decisions．
In a second study，15 elderly people who completed a 6-month aerobic-training course were fas-ter at attention tasks compared with 14 seniors who just did stretching and toning exercises for the same amount of time．
So，even going for a walk every 2 or 3 days forjust 10 to 45 minutes can help．That should be good news for your grandparents．
The effects of exercising on the brains of younger people haven't been studied yet．Still，it can't hurt to take occasional study breaks and go for a walk or run around with your friends．You might even do better in school．
Whatever you do，though，don't try to read and walk at the same time．You could end up hurting yourseff!
31．Walking regularly helps elderly people_______．
A．lose weight
B．become happier
C．concentrate better
D．look younger
32．After taking exercise for a few weeks，the mice were found to have_____．
A．higher blood pressure
B．faster heartbeat
C．more blood flow to the brain
D．better appearance
33．The first study on 41 elderly people found______．
A．the less-fit participants did arrow tasks faster
B．the fitter participants did arrow tasks faster
C．the less-fit participants gave more accurate answers
D．the fitter participants gave more accurate answers
34．It can be good for health when one takes a walk every 2 or 3 days for at least______．
A．3 minutes
B．45 minutes
C．30 minutes
D．10 minutes
35．It is suggested in the last paragraph that people should______．
A．run around once a week
B．not read and walk at the same time
C．go for a walk every day
D．not hurt their friends while exercising
参考答案及解析
31．C [解析]本题是细节考查题。题目是老年人经常运动有助于以下哪项。原文是第二段"对老年人的新研究显示经常运动能让老年更集中精力"。选项A"减肥"；选项B"更愉快"；选项C"精力更集中"；选项D"显得年轻"。因此只能选C。
32．C [解析]本题是细节考查题。原文是第三段"以前的研究证明老鼠在轮子上奔跑数周后它们的学习、记忆和集中程度都有所提高。运动的老鼠大脑中的血液流量大于不运动的，而它们脑细胞的联系也更频繁。"选项A"更高的血压"；选项B"更快的心跳"；选项C"有更多血液流经大脑"；选项D"更好的外表"。因此只能选C。
33．B[解析]本题是细节考查题。原文是第五段"研究员发现身体健康的成年人完成箭头测试的速度更快，他们的答案和身体状况不佳的参加者一样准确。"选项A"身体状况不佳的参赛者完成箭头测试更快"；选项B"身体健康的参赛者完成箭头测试的速度更快"；选项C"身体状况不佳的参赛者在箭头测试中答案更准确"；选项D"身体健康的参赛者在箭头测试中答案更准确"。因此只能选B。
34．D [解析]本题是细节考查题。原文是第七段"因此每两到三天仅仅出去散步10到45分钟都会对健康有益。"因此只能选D。
35．B[解析]本题是细节考查题。原文是最后一段"不管你怎么做都不要一边走路一边读书，你有可能伤到自己的哦"。选项A"一周跑一次步"；选项B"不要同时走路和读书"与原文内容一致；选项C"每天散步"；选项D"运动时不要伤着朋友"。因此答案选B"。
