题干

在“探究阳光在植物生长中的作用”实验过程.下列说法正确的是(  )

A:暗处理是将植物放在黑暗处24小时

B:部分遮光的实验操作不必要,因为已经进行了暗处理

C:酒精脱色后,大烧杯内的清水呈绿色,小烧杯内酒精无色

D:滴加碘液和显色以后,叶片上用黑纸片遮光的部分呈蓝色

上一题 下一题 0.0难度 选择题 更新时间:2017-06-12 12:43:22

答案(点此获取答案解析)

A

同类题2

阅读理解

    Teachers in some secondary schools in Britain are worried that their job may become impossible shortly unless something can be done to restore discipline in the classrooms. In the problem schools, mostly in large cities, a small minority of teenage pupils disturb lesson to such an extent that the teacher can no longer teach their classes effectively.

    Some people consider that the permissive (随意) nature of modern society is responsible for such kind of behavior. Small children who are continuously encouraged to express themselves without reservation are naturally unwilling to accept school discipline when they grow older. Furthermore, modern teaching techniques) which appear to stress personal enjoyment at the expense of serious study work, might be teaching the child to put his own interests before his duties to the community in which he lives.

    Perhaps the problem can be solved by improving facilities for the moral guidance of these difficult children or by better cooperation between the schools and the parents—for the parents may be mainly responsible for the bad behavior of their youngsters. Violence at home, violence and crime on TV make some children turn violence themselves.

    But some of the teachers believe that there ought to be a return to more “old fashioned” methods. At present, in some school teachers are even not allowed to punish a child who does something bad and wrong. Physical punishment is not permitted now. People are too soft on children these days. It seems that children can do whatever they like at school while the teachers can't do anything to punish them. I don't know why the schools authority abandoned some of the effective punishments that worked well. Things like that didn't happen when we were at school because the teachers kept those problem students under control by using a stick.

同类题4

阅读理解

    On a recent visit to the Museum of Modem Art with a friend and her daughter,wandering through the museum's exhibits,I was struck by how often my friend's 13-year-old daughter asked us to take photos of her with her smart phone in front of the artwork.Then,she gazed at the photos which she would then post on Instagram,Snapchat and all the rest.She was not the only person who was doing this; it seemed everyone was busy taking photos of themselves "experiencing" the museum.

    This is by no means a criticism of my friend's daughter or anyone else.What was concerning,at least to me,was that in between being photographed and posting,my friend's daughter had no interest in the artwork,a fact which didn't seem to matter or have anything to do with wanting to post herself as someone enjoying the experience.

    When I was her age,I had no interest in going to museums either.Having no interest in art at her age (and any age) is completely normal.But what is disturbing is how much of a young person's energy these days goes into creating an image of the life they're living and the character they "are" in that life.While creating a self-image has always been a big part of growing up and figuring out our identity,social media seems to have changed the rules of the game.Social media has not just increased the pressure and possibility of creating a self-generated(自我创造的)  self-image,but also distorted(歪曲)the process through which we become who we are.Young people now seem to be creating an image of who they are in place of becoming who they are,posting their life rather than living it.

    Social media has turned life and its experiences into an exercise in narcissism(自恋,自我陶醉).No matter what the experience is actually about,it becomes about you,the person who is living it.A concert is not about the music,a restaurant not about the food and a sport event not about the sport;it's all about you,the doer,and what the event says about you.As a result the more we use life create an identity,the more distant from life we feel.Instead of being part of it,we feel as if we have to keep generating new life material.

    I hope the next time you post your story,pause for a moment and experience where you are,feel what it feels like to live what you're living without using life for your benefit,or for anything at all.Just live,without the narrative(叙述).While you may feel this practice is a threat to your identity,causing you to miss a chance to prove your value,in fact,the benefit will far outweigh any loss it brings.