问题 单项选择题

关于酶活性中心的叙述,正确的是

A.所有的酶都有活性中心

B.所有酶的活性中心都有辅酶

C.所有酶的活性中心都有金属离子

D.酶的必需基团都位于活性中心之内

E.所有的抑制剂都是作用于活性中心

答案

参考答案:A

阅读理解

We know health and happiness are important in everyone’s life. Here are some ways to make them easy.

Eat a balanced diet(平衡饮食). Eat a lot of fruit and vegetables, some grains(谷物) and a little meat.

Exercise twice or three times a week.

Get enough sleep. It is best to get eight hours’ sleep a day.

Keep yourself busy. This is good because it stops you from having bad habits. To keep yourself busy, you can walk around the house, spend time with your pets, do a sport, or do a hobby you enjoy.

Go out and make friends. Spend time and have fun with them. Talk with them, but you must be sure not to talk about anything bad. You should stay with the people who are healthy and happy themselves.

小题1:How often should you exercise if you want to get health and happiness?

A.Every day .

B.Twice a day

C.Twice or three times a week .

D.Three times a month.小题2:How many hours do you need to sleep every day?

A.Seven.

B.Eight.

C.Nine.

D.Ten小题3:The underlined word “it”referes to (指的是)“     ”.

eating a balanced diet.  B.exercising more  C. keeping yourself busy  D.making friends

小题4:Whice of the following is NOT true?

A.We should eat a lot of meat to keep healthy.

B.We should exercise to keep healthy.

C.The people whom we make friends with must be healthy and happy themselves.

D.We can spend our free time doing a sport or doing hobby we enjoy.小题5:Which is the best title(标题) for the passage?

A.Eating Habit

B.Healthy Lifestyle

C.Making friends

D.Ways to Have Health and Happines

多项选择题