问题 选择题

某果园的苹果树大都产量较低、果实品质欠佳,若要尽快更新为优质苹果树,提高果实的品质和产量,你认为最好应采取下列哪一措施?                      (  )

A.果枝扦插

B.果枝嫁接

C.种子繁殖

D.全部换栽

答案

答案:B

此题考查的是嫁接,嫁接是指把一个植物体的芽或枝,接在另一个植物体上,使结合在一起的两部分长成一个完整的植物体,嫁接属于无性繁殖,没有精子和卵细胞结合成受精卵的过程,因而后代一般不会出现变异,能保持嫁接上去的接穗优良性状的稳定,使果树提早结果,增强抵抗力,而砧木一般不会对接穗的遗传性产生影响,因此苹果、桃等果木的繁殖常采用嫁接技术,嫁接技术可以帮助尽快的更新果木的品种。

阅读理解

阅读理解。

     On the first day of class, Smith's foreign students fill in forms and give the information about themselves.

     Name: Claude

     Country: Germany (德国)

     Native Language (本族语): German

     Time in the USA: 9 months

     Family: I live with my parents.

     Work: I used to be an art teacher in Germany. But now I'm working in a company.

     Interests: I love painting. I like music, too.

     Name: Li Ming

     Country: China

     Native Language: Chinese

     Time in the USA: 2 years

     Family: I have one son. He is studying in China. My wife is an English teacher.

     Work: I was a math teacher, but now I'm a cook.

     Interests: I like cooking. I also like sports, such as basketball, table tennis and so on.

     Name: Carolina

     Country: Russia

     Native Language: Russian

     Time in the USA: 4 years

     Family: I live with my husband and 2 children.

     Work: I was a basketball player, but now I'm a teacher.

     Interests: I love sports. I like traveling.

     Name: Kalumi

     Country: Japan

     Native Language: Japanese

     Time in the USA: 3 months

     Family: My family, my parents and 4 brothers and sisters, all live in Japan. I'm here by myself.

     Work: I worked as a nurse in my country. Now I'm a shop assistant.

     Interests: I like such activities as reading, drawing and watching TV.

1. ______ has lived in America for the longest time among the four persons.

A. Kalumi

B. Carolina

C. Claude

2. ______ used to be teachers in their own countries.

A. Li Ming and Claude

B. Li Ming and Carolina

C. Kalumi and Claude

3. Of the four persons, ______ has a big family.

A. Claude

B. Carolina

C. Kalumi

4. ______ like sports.

A. Claude and Li Ming

B. Carolina and Kalumi

C. Li Ming and Carolina

5. These persons will ______ together.

A. draw pictures

B. study in the same class

C. teach English

单项选择题