题干

关于粒子和宇宙,下列认识正确的是(  )

A:宇宙是一个有层次的天体结构系统,恒星是绝对静止的

B:在水分子、氢原子和电子等粒子中,尺度最小的是氢原子

C:原子由带正电荷的原子核和带负电荷的电子构成

D:红墨水在水中散开说明分子间有引力还有排斥力

上一题 下一题 0.0难度 选择题 更新时间:2019-06-18 11:44:46

答案(点此获取答案解析)

C

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    You might make a disgusted face when you notice that the person waiting in their car at the red light next to you is picking their nose,but admit it,you do it too.And while it might be the natural option when there isn't a box of tissues around,it can be bad for you.The main reasons people feel the need to pick their nose is to clear it of dried liquid,stop an itch(痒),or just because it feels good.Boogers(鼻屎)form when dried liquid and cilia,the tiny hairs that line the nostrils(鼻孔),trap the dust,dirt,and other things.When boogers build up in your nose,it can be uncomfortable,and sometimes just blowing into a tissue doesn't do the trick.

    Otolaryngologist Erich P.Voigt, MD ,told Business Insider that picking your nose can cause injuries and bleeding within your nostrils.That's not terribly damaging,but when the bacteria from your hands get into your body,it can cause a cold and flu.So doctors strongly suggest not picking the nose.

    If dry winter air is causing the dirty liquid to harden in your nostrils,making you want to pick,consider damping the air at home,or taking a steam shower to soften things up in there.

    Children, who are most famous for having a finger up their nose,sometimes don't realize how much injury they're causing,and sometimes it.can lead to nose bleeds.

    So, next time you go to pick your nose,think about how many bacteria are on your hands and in your boogers, and maybe reach for a tissue instead.Even if you 're alone,and not waiting for the light to turn green,please,use a tissue.