问题 填空题

化学可以帮助人类认识改造周围的世界,促进社会发展.

糖类、油脂、蛋白质和维生素都是人类的基本营养物质.下表为某品牌燕麦片标签中的一部分.

每100g含有

营养成分

糖类油脂蛋白质维生素C
7.6g7.8g7.4g18mg201mg18.2mg30.8mg8.1mg
①燕麦片的营养成分中能与水反应生成氨基酸的营养物质是______;大量存在于新鲜蔬果的是______;能促进人体骨骼生长发育的元素是______.

②维生素C易溶于水,向其水溶液中滴入紫色石蕊试液,石蕊变红色,加热该溶液至沸腾,红色消失.因此,烹调富含维生素C的食物时,应该注意______;在碱性条件下,维生素C易被空气氧化,烧煮时最好加一点______.

答案

①蛋白质在人体内酶的催化作用下,与水发生水解反应,最终生成氨基酸;维生素主要存在于蔬菜和水果中;钙主要存在于骨胳和牙齿中,使骨和牙齿具有坚硬的结构支架,缺乏幼儿和青少年会患佝偻病,老年人会患骨质疏松.

②根据题中的信息“向其水溶液中滴入紫色石蕊试液,石蕊变红色,加热该溶液至沸腾,红色消失”可知,维生素C化学性质不稳定,在加热条件下易分解,根据信息“在碱性条件下,维生素C易被空气氧化”知,在酸性条件下,维生素C不易被氧化,故烹调富含维生素C的食物时,应该注意不要高温加热,烧煮时最好加一点食醋.

故答案为:①蛋白质;维生素;钙;②不要高温加热;食醋.

阅读理解

阅读理解。

      "Cool" is a word with many meanings. Its oldmeaning is used to express temperature that is a lit-tle bit cold. As the world has changed, the wordhas had many different meanings.    

      "Cool" can be used to express feelings aboutalmost anything.        

      When you see a famous car in the street, may-be you'Il say, "It's cool. " You may think "he's socool"

when you see your favourite footballer.     

     We all maximize (扩大)  the meaning of "cool".  You can use it instead of many words suchas "new" or "surprising". Here's an interestingstory we can use to show the way how the word isused. A teacher asked her students to write aboutthe waterfall (瀑布)  they had visited.  On onestudent's paper was just one sentence(句子) ,"It'sso cool. " Maybe he thought it was the best way toshow what he saw and felt.      

      But the story also shows a scarcity(缺乏) ofwonds. Without "cool", some people have nowords to show the same meaning. Can you think of many other words that make your life colorful as the word "cool" ? I can.  And I think they are also verycool.

1. We know that the word "cool" has had ______.

A. only one meaning

B. no meanings

C. many different meanings

D. the same meaning

2. In the passage, the word“express”means"______".

A. see

B. show

C. know

D. feel

3. If you are ______ something, you may say, "It’s cool."

A. interested in

B. angry about

C. afraid of

D. unhappy with

4. The writer takes an example to show he is ______ the way the word is used.

A. pleased with

B. strange to

C. worried about

D. careful with

5. In the passage, the writer suggests(暗示)that the word "cool"______.

A. can be used instead of many words

B. usually means something interesting

C. can make your life colourful

D. may not be as cool as it seems

多项选择题