问题 多项选择题

如图甲表示神经元的部分模式图,图乙表示突触的局部模式图,下列叙述错误的是()

A.兴奋在反射弧中传递是单向的,其原因是兴奋在图乙所示结构上不能由①→②传导

B.若给图甲箭头处施加一强刺激,则电位计会先右后左偏转两次

C.突触小泡内的神经递质释放到突触间隙的方式是主动运输,需要线粒体提供能量

D.人在拔牙时,往往需要在相应部位注射局部麻醉药,使其感觉不到疼痛,这是因为麻醉药最可能暂时阻断了传入神经的兴奋传导

答案

参考答案:B, C

解析:兴奋在反射弧中是单向传递的,依次是感受器、传入神经、神经中枢、传出神经、效应器,主要原因是在突触上传递是单向的,只能由突触前膜传向突触后膜,图中含有突触小泡的②是突触前膜,①是突触后膜,兴奋在图乙所示结构上不能由①→②传导,A正确;若给图甲箭头处施加一强刺激,则电位计会先左后右偏转两次,B错误;突触小泡内的神经递质释放到突触间隙的方式是胞吐,需要线粒体提供能量,C错误;人在拔牙时,往往需要在相应部位注射局部麻醉药,使其感觉不到疼痛,这是因为麻醉药最可能暂时阻断了传入神经的兴奋传导,D正确;答案是BC。考点:本题考查神经调节的相关知识,意在考查考生理解所学知识的要点,把握知识间的内在联系的能力。

单项选择题
阅读理解

Hundreds of secondary schools are using a controversial reward scheme which “bribes” (贿赂)pupils with iPods and DVD players to turn up in classes and do homework.

Almost one million schoolchildren have been issued with supermarket-style reward cards which allow them to collect good-behavior “points” and cash them in for prizes.

Schools taking part in the “Vivo Miles” scheme are spending several thousand pounds a year in an attempt to cut truancy (逃学) and promote achievements. The prizes are ultimately funded by the taxpayer, through school budgets. Nearly 500 secondary schools, one in six, have decided to take part in the scheme, which is intended to replace old-style rewards such as stickers and golden stars.

But the extent of rewards being offered in schools brought a warning that a generation of children is growing up expecting to be rewarded at every stage. Many youngsters are collecting points for ordinary achievements such as remembering to bring their PE kit and wearing the correct uniform.

Under the scheme, teachers award Vivo points—worth 1 penny each—according to the school’s policy. Schools typically spend£4 to£6 on prizes per pupil each year, although some commit considerably more. Most pupils accumulate between 400 and 600 Vivos a year. Vivo Miles insists it is “pretty rare” for a pupil to accumulate enough points to buy an iPod, which requires 3,100 Vivos.

But Chris McGovern, chairman of the Campaign for Real Education, said the scheme amounted to “bribery”. “It misleads children into thinking anything which requires effort has to have a special reward,” he said. “This ‘all must have prizes’ view is damaging to children in the long-term.” The scheme amounted to an “admission of failure” by schools. He said. “It shows a school has failed to convince children education is important.”

小题1:The “Vivo Miles” scheme is aimed at ______________.

A.increasing the income of the school

B.encouraging students to perform well at school

C.inviting more students to attend the school nearby

D.encouraging parents to donate to the school小题2:The underlined word “controversial” in the first paragraph can be replaced by __________.

A.arguable

B.practical

C.strange

D.mature小题3:Those who oppose the “Vivo Miles” scheme think ______________.

A.it helps control the problem of truancy

B.it teaches children the importance of saving

C.it will mislead children about efforts and rewards

D.it’s not easy to get more than 600 Vivos a year小题4:What’s the writer’s attitude towards the scheme?

A.Supportive.

B.Opposed.

C.Unconcerned.

D.Objective.