题干

同一植株的不同器官或同一器官不同部位生长素浓度往往不同.甲图是一株盆栽植物,乙图表示该植物不同器官对生长素浓度的反应.据图回答下列问题(要求:用乙图根、茎、芽三条曲线上相应字母所对应的浓度来表示甲图相应各点的生长素浓度):

(1)乙图____ 点浓度可表示甲图①处生长素浓度____ 点表示②处生长素浓度.

(2)将该植物较长时间置于右侧光照下,乙图____ 点浓度可表示③侧生长素浓度;____ 点表示④侧生长素浓度.此时,植物茎将____ 生长.

(3)能够促进茎生长的浓度范围是____ mol•L1

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b或d   ,f,g或k,c,向右(向光)弯曲,1010~10﹣2

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    Research suggests that at least 64% of people now spend up to four hours daily of spare time in front of a screen. Just as TV watching has been linked to higher chances of being fat and getting diseases, this extra sedentary time is bad news for our health.

    ⒈Choose outdoor activities over technology

    When you're at home, make it a rule that you can't be online if the sun is shining. Instead, you have to go for a walk, ride a bike, swim or get some other kind of healthy, physical activity for at least an hour before you can pull out your phone or tablet, or take a seat at the computer. This rule should be fit for everyone in your family.

    ⒉Limit social media use

    Social networks have changed computer and mobile use for people of all ages. Whether it's Facebook, Twitter, Instagram or Snapchat. Limit the amount of time you spend on social media. Avoid aimless browsing(浏览) and give your time online a purpose research holidays or catch up on the news of the day. Then log off.

    ⒊Save time for reading

    Challenge yourself to read at least 30 pages of a great book before you check your computer or mobile phone. Pick the right reading material and you'll soon find you've discovered an enjoyable pastime.

    ⒋Create projects for yourself

    It's amazing how much you can achieve when you're not glued to (长时间盯着) a screen. Do a list of one-hour evening projects. Some suggestions are organizing kitchen cupboards, cleaning your bedroom. Then try to do one each evening.