2005年考研英语真题和解析(1).pdf

2005年全国硕士研究生入学统一考试英语试题 SectionI UseofEnglish Directions: Readthe followingtext.Choosethebest word(s) for each numberedblank andmark [A], [B], [C] or [D] on ANSWER SHEET 1(10points) Thehuman nose is an underratedtool.Humans are often thought tobe insensitive smellers comparedwith animals, 1this islargely because,2animals,we standupright.Thismeansthat our noses are 3toperceiving those smellswhich float through the air,4 themajority of smellswhich stick to surfaces.In fact, 5 ,we are extremely sensitiveto smells, 6we donot generally realize it.Our noses are capable of 7human smells even when these are 8to far below onepart in onemillion. Strangely, somepeople findthat they can smell onetype of flower but not another, 9 others are sensitive tothe smells ofboth flowers.Thismay bebecause somepeople donot havethe genesnecessary to generate 10 smell receptorsin thenose.Thesereceptors arethe cellswhich sense smells and send 11tothebrain.However, it has been foundthat even peopleinsensitive to a certain smell12 can suddenly become sensitive to it when 13to it often enough. The explanation for insensitivity to smell seemstobethat brain findsit 14 tokeep all smell receptorsworking all thetimebut can 15new receptorsifnecessary.Thismay 16 explain why we arenot usually sensitive to our own smells—we simply donot needtobe.We arenot 17 oftheusual smell of our own house,but we 18new smells when wevisit someone else’s.Thebrain findsit best tokeep smell receptors 19 for unfamiliar and emergency signals20the smell of smoke,which might indicatethe danger of fire. 1.[A] although [B] as [C]but [D]while 2.[A] above [B]unlike [C] excluding [D]besides 3.[A] limited [B] committed [C] dedicated [D] confined 4.[A] catching [B] ignoring [C]missing [D] tracking 5.[A] anyway [B] though