题干

下列关于实验“土壤中小动物类群丰富度的研究”的说法中,不正确的是(   )

C:利用小动物的避光避热性,收集样土中的小动物可采用带灯罩的热光源

A:为了调查不同时间土壤中小动物丰富度,可分别在白天和晚上取同一地块的土样

B:许多土壤小动物有较强的活动能力,可采用标志重捕法调查土壤小动物类群丰富度

D:对于无法知道名称的小动物,不可忽略,应记录下它们的特征

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B

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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.