问题 解答题

菜豆和玉米种子的结构相同点是都是由外面的______和里面的胚两部分组成,胚又是由______、______、______和______组成.不同点是玉米种子还有______和______.

答案

菜豆种子由种皮和胚两部分组成,玉米种子由种皮、胚和胚乳三部分组成,胚由胚芽、胚轴、胚根和子叶组成,菜豆种子和玉米种子结构上的相同点和不同点如图所示:菜豆和玉米种子的结构相同点是都是由外面的种皮和里面的胚两部分组成,不同点是玉米种子还有胚乳和一片子叶.

故答案为:种皮;胚芽;胚轴;胚根;子叶;胚乳;一片子叶

阅读理解

阅读理解

     The summer vacation is over. It's true that time always flies fast. During the vacation, the weather

was hot and I could not do much work, but I lived happily.

     As the afternoon was hot, I did my work in the morning. I used to get up at 6:30 and take a walk

in the garden for half an hour. After breakfast, I began reading English and Chinese and worked on

some maths problems. These took me three hours or more. I worked quite hard and made good

progress(进步).

     I spent the afternoon outside. I went to swim and it was fun. I would not go home until it was about

five or six o'clock. Sometimes a friend of mine would come to see me and we would spend some hours

listening to music.

     In this way I spent my vacation happily. And I not only made up some of my lessons, but also

became a good swimmer. Now I am in good health and high spirits.

1. What does the text mainly tell us?

A. How the writer spent his summer holidays.

B. What the weather was like that summer.

C. How the writer learned to swim.

D. Where the writer took a walk

2. How long did it take the writer to study?

A. Half an hour

B. Three hours or more

C. Only one hour.

D. Two hours and a half.

3. The writer spent most of the afternoon __________.

A. listening to music

B. visiting his friend

C. walking in the garden

D. swimming

4. The writer had very good summer holidays because he __________.

A. worked hard at everything

B. learned to swim and did his work well

C. got up early and went home late

D. liked swimming better than studying

5. Which of the following is not true?

A. The writer made progress in his lessons.

B. The writer took a walk for half an hour before breakfast.

C. The writer began studying as soon as he got up.

D. The writer spent more time swimming than listening to music.

选择题