题干

人体中水的含量约占65%,下列选项中能正确说明水对人体重要性的是(  )

①水和糖类、脂肪、蛋白质一样,为人体提供能量;

②没有水,人体内大部分化学反应就根本不会发生;

③水的比热小,有利于维持体温;

④体内营养物质的运输离不开水.

A:①②

B:②③

C:②④

D:③④

上一题 下一题 0.0难度 选择题 更新时间:2019-07-14 04:10:41

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C

同类题1

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Dear Karen,

    As you probably know, it's my sister Suzie's 16th birthday in a week. We're planning a surprise party for her. Julie's going to pick her up from school as usual on Friday but she's not taking her home. She’s bringing her to the Palace Hotel, the big modern one near the station. We're having a meal there and we've also hired (租用) the ballroom (舞厅) for a party in the evening. I hope you can come!

    All her friends from school are coming and quite a few of the people from our village, too. Of course, Mum and Dad are coming up from England and I've managed to persuade (说服) our other sister, Marie, to come over from Australia. She's bringing her kids with her, too.

    After the party we're going to have another one on Saturday! Well, not really a party. We're inviting the family and close friends (that includes you) for a meal at the house. If the weather is nice, we'd like to have a barbecue in the garden. Julie's going to make a special cake for Suzie.

    Anyway, we hope to make it a really special weekend for Suzie. On Sunday we're all going for a walk in the country. You know how she loves walking and we're all going to need a bit of exercise after all that lovely food. We're hoping to go up to the lake. Marie said she wanted her kids to feed the ducks just like Suzie and she did when they were very young. I'm sure Suzie will love that too.

    It would be great if you could come over for the weekend. We would all love to see you. Let me know as soon as you can.

Best,

David

同类题3

阅读下文,回答相关问题。 

                                                                             学会看病   
      ①儿子比我高了。
      ②一天,我看他打蔫,就习惯地摸摸他的头。他猛地一偏脑袋,表示不喜欢被爱抚。但我已在这一瞬的触摸中,知道他在发烧。
      ③“你病了。”我说。“噢,我还以为是睡觉少了呢。妈妈,我该吃点什么药?”他问。
      ④孩子一向很少患病,居然连得病的滋味都忘了。我刚想到家里专储柜里找体温表,突然怔住。因为我当过许多年的医生,孩子有病,一般都是自己在家就治了。他几乎没有去过医院。
      ⑤“你都这么大了,你得学会生病以后怎么办。”我说。
      ⑥“我早就知道生病以后怎么办。找你。”他成竹在胸。“假如我不在呢?”“那我就……就找我爸。”
      ⑦也许这样逼问一个生病的孩子是一种残忍。但我知道总有一天他必须独立面对疾病。既然我是母亲,就应该及早教会他生病以后该怎么办。
      ⑧“假如你最终也找不到你爸呢?”“那我就忍着。你们早晚会回家。”儿子说。“有些病是不能忍的,早一分钟是一分钟。得了病以后最应该做的事是上医院。”“妈妈,你的意思是让我今天独自去医院看病?”他说。在病中,孩子依然聪敏。“正是。”我咬着牙说,生怕自己会改变主意。“那好吧……”他扶着脑门说,不知是虚弱还是思考。“你到外面去‘打的’。然后到××医院。先挂号,记住,要买一个本……”我说。“什么本?”他不解。“就是病历本。然后到内科,先到分号台,护士让你到几号诊室你就到几号,坐在门口等。查体温的时候不要把人家的体温表打碎……”我喋喋不休地指教着。“妈妈,你不要说了。”儿子沙哑着嗓子说。
      ⑨我的心立刻软了。是啊,孩子毕竟是孩子,而且是病中的孩子。我拉起他滚烫的手说:“妈妈这就领着你上医院。”他挣开来,说:“我不是那个意思,我是说我要去找一支笔,把你说的这个过程记下来,我好照着办。”
      ⑩儿子摇摇晃晃地走了。从他刚出门的那一分钟起,我就开始后悔。我想我一定是世上最狠心的母亲,在孩子有病的时候,不但不帮助他,还给他雪上加霜。我就是想锻炼他,也该领着他一道去,一路上指指点点,让他先有个印象,以后再按图索骥。虽说很可能留不下记忆的痕迹,但来日方长,又何必在意这病中的分分秒秒。
      ⑪时间艰涩地流动着,像沙漏坠入我忐忑不安的心房。两个小时过去了,儿子还没有回来,我虽然知道医院是一个缓慢的地方,心还是疼痛地收缩成一团。
      ⑫虽然我几乎可以毫无疑义地判定儿子患的只是普通的感冒,如果寻找什么适宜做看病锻炼的病种,这是最好的选择,但我还是深深地谴责自己。假如事情重来一遍,我再也不会教他独自去看病。万一他以后遇到独自生病的时候,一切再说吧。我只要这一刻他在我身边!
      ⑬终于,走廊上响起了熟悉的脚步,只是较平日有些拖沓。我开了门,倚在门上。
      ⑭“我已经学会了看病。打了退烧针,现在我已经好多了。这真是件挺麻烦的事。不过,也没有什么。”儿子骄傲地宣布。又补充说:“你让我记的那张纸,有的地方顺序不对。”
      ⑮我看着他,勇气又渐渐回到心里。我知道自己将要不断地磨炼他,在这个过程中,也磨炼自己。
      ⑯孩子,不要埋怨我在你生病时的冷漠。总有一天,你要离我远去,独自面对包括生病在内的许多苦难。我预先能帮助你的,就是向你口授一张路线图。它也许不那么准确,但聊胜于无。
                                                                                                                                                          (作者:毕淑敏 选文有删改)