问题 单项选择题

经实验检测出某一植株的不同器官对不同生长素浓度的反应如图所示,横坐标表示生长素物质的量浓度。根据实验结果,可以获得的结论之一是()。

A.当生长素浓度为10-9mol·L-1时,抑制根的生长,促进芽的生长

B.根向地生长的原因是其背地侧生长素浓度高于10-8mol·L-1

C.低浓度生长素促进根、芽的生长,高浓度生长素则促进茎的生长

D.若解除顶端优势,应确保侧芽生长素浓度低于10-6mol·L-1

答案

参考答案:D

阅读理解

阅读理解。

Dear Alice,

     Thank you for your last letter. I like reading it very much.

     Thank you for telling me about your school life. In this letter I'll tell you about my life.

     My day starts at 6:30 am. I get up and run before breakfast. I only have a small breakfast.  I can't eat much in the morning-just a piece of bread and a cup of coffee. At 7:00 I take a bus and get to school at

half past seven. I study five days a week, from Monday to Friday. I'm very busy every day. I have seven

classes, four in the morning and three in the afternoon. I study sci- ence, biology, math, French, English,

music, P.E. ,art and American history.  I like French and eat lunch in the dining room of our school.  I like all my teachers.  They are very kind, but our P. E. teacher is a little strict. Sometimes he makes us tired.

Classes are over at 4:30. Then I do my homework. On weekends I join a music club. I play the drums in

a rock band. I think it's really interesting.

                                                                                                                                                  Love,

                                                                                                                                                 Mary

1. Who writes this letter?

A. Alice.

B. Mary.

C. Alice and Mary.

D. Mary's cousin.

2. What time does Mary get up?

A. At 6:00 am.

B. At 6:30 am.

C. At 7:00 am.

D. At 7:30 am.

3. How many classes does Mary have in the afternoon?

A. Seven.

B. Four.

C. Eleven.

D. Three.

4. What's Mary's favorite subject?

A. Math and French.

B. American history.

C. Music.

D. French and Music.

5. Where does Mary have lunch?

A. At home.

B. At school.

C. At work.

D. In a shop.

多项选择题