问题 选择题

下列有关说法中,正确的是(  )

A.糖类、蛋白质在一定条件下都能发生水解反应

B.洗衣粉、橡胶、阿司匹林都只能由人工合成得到

C.稀双氧水可用于清洗伤口,以达到杀菌、消毒的目的

D.变质的油脂有难闻的特殊气味,是因为油脂发生了水解反应

答案

A、糖类中的葡萄糖属于单糖,是不能水解的糖,故A错误;

B、自然界中存在天然橡胶,其主要成分为聚合物,故B错误;

C、双氧水具有氧化性,稀双氧水可用于清洗伤口,可以杀菌、消毒,故C正确;

D、油脂中含有不饱和键,能被氧化剂氧化,变质的油脂有难闻的特殊气味,是因为油脂被氧化而变质的缘故,故D错误.

故选C.

阅读理解

阅读理解。

    On the first day of school our professor introduced himself and challenged us to get to know someone

we didn’t know. I stood up to look around when a gentle hand touched my shoulder(肩膀). “Hi, girl!

My name is Rose, I’m 87 years old.”

   “Why are you in college at such a young age?” I asked jokingly.

   “I always dreamed of having a college education and now I’m getting one!”she replied.

    Rose became a college symbol(象征) this year and she easily on her from the other students.

    At the end of the semester we invited Rose to speak at our football party. I’ll never forget what she

taught us.

   “We do not stop playing because we are old; we grow old because we stop playing. There are only

two secrets to staying young, being happy and achieving success. You have to laugh and find humor(幽

默) every day. You’ve got to have a dream. When you lose you dreams, you die!”she said.

   “There is a huge difference between growing older and growing up. If you are nineteen years old and

lie in bed for one full year and don’t do anything, you will turn 20 years older. If I am 87 years old, and

stay in bed for a year, and never do anything, I will turn 88. Anybody can grow older. But every minute

counts for young men,” she added.

    She ended her speech by singing The Song of Rose. She challenged each of us to study the lyrics and

live then out in our daily lives.

    At the year’s end, Rose finished the college education she had begun all those years ago. One week

after graduation Rose did peacefully in her sleep.

1. Rose went to college because she         .

A. wanted to live longer

B. loved to stay with the young

C. wanted to realize her dream

D. planned to enjoy her life there

2. From the story we can see that Rose was____ during her stay in college.

A. outgoing and popular

B. brave and hard-working

C. honest and athletic

D. calm and creative

3. Which of the following is included in Rose’s speech?

A. People won’t grow old if they stop playing.

B. The more you laugh, the younger you will be.

C. People easily become old if they do more things.

D. Time is especially important for young people.

4. At the end of her speech, Rose asked each of her classmates          .

A. to sing along with her

B. to sing one’s own song

C. to recite the lyrics

D. to do as the lyrics said

5. Which of the following can best describe the story?

A. Live with your dream.

B. Find secrets of staying young.

C. Learn wherever you are.

D. Be happy every day.

单项选择题