题干

下列有关植物蒸腾作用的叙述,错误的是(  )

A:蒸腾作用越强,根对无机盐和水的吸收速度越快

B:移栽植物时去掉部分枝叶、遮阳和选择阴雨天,能降低蒸腾作用,提高成活率

C:干旱地区植物的叶片往往较小,这反映了生物对环境的适应

D:蒸腾作用的强弱受光照强度、湿度等环境因素的影响

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A

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    Love to sink into your chairs and relax when you get to school? Then you will not be happy to hear that schools all over the world are seriously considering exchanging traditional desks for ones with no seats at all — Yes, that means you will be encouraged to stand through those already too long math and science lessons! Why would anyone even think of putting kids to such cruelty? Experts say it improves their health and helps fight obesity. While that may seem a little far-fetched (牵强的), the officials at the few schools around the world seem to agree.

    Among them are educators from the College Station Independent School District in Texas, who recently completed aweek-long experiment involving 480 students across three elementary schools. The 374 kids that agreed to participate in the study were provided with adevice that helped record step count and calorie consumption over the entireperiod.

    All 25 teachers involved in the study reported that students appeared to be more alert and concentrate better, when allowed to stand. The one thing that did surprise the researchers was that younger kids were more willing to stay standing than kids in higher grades. They believe this may have something to do with the fact that after years ofbeing asked to “sit still”, older kids have a harder time adjusting to this unexpected freedom.

    American schools are not the only ones reporting success with stand-up desks. Four Catholic schools in Perth,Australia, which have been testing them since October 2013, have seen similar results. In May 2014, Grove House Primary School in Bradford, West Yorkshire,became Europe's first test one, with a seven-week trial that involved the useof desks made by Ergotron in their fifth-grade classrooms. While official results are not out yet, early reactions from both teachers and students, have been extremely encouraging.

    The findings of these studies and othersdone previously, all seem to mean that allowing kids to move around in classrooms is a win-win for students and teachers — it helps kids get healthier and provides educators with a more engaged audience.