问题 选择题

胎儿与母体进行物质交换的结构是(  )

A.卵巢

B.输卵管

C.羊水

D.胎盘

答案

由卵细胞到胎儿的过程是:卵细胞→受精卵→胚泡→胚胎→胎儿,受精卵在女性的输卵管内形成,受精卵不断进行分裂,逐渐发育成胚泡;胚泡缓慢地移动到子宫中,最终植入子宫内膜,这是怀孕;胚泡中的细胞继续分裂和分化,逐渐发育成胚胎,并于怀孕后8周左右发育成胎儿,胎儿已具备人的形态;胎儿生活在子宫内半透明的羊水中,通过胎盘、脐带与母体进行物质交换;怀孕到40周左右,胎儿发育成熟,成熟的胎儿和胎盘一起从母体的 * * 排出,即分娩.

故选D.

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完形填空。

     There are some special traditions in Hawaii. People are very friendly and always welcome

visitors. They give visitors a lei, a long necklace of beautiful fresh flowers. Men wear bright

flowered shirt and women often wear long flowered dresses. There are traditional Chinese,

Japanese and Filipino holidays and all the holidays from the United States. They call Hawaii

the Aloha State. Aloha means both hello and goodbye. It also means " I love you".

     Usually when people from different countries, races and traditions live together, there are

serious problems. There are so many people  living in  Hawaii, but in general, people have

learned to live together in peace.

     Hawaiians get most of their money from visitors, and most of the visitors come from the

mainland and from Japan. There are so many people living in Hawaii now that there are

residential areas ( 住宅区 ) where there used to be farms. Some of the big sugar and pineapple

companies have moved to the Philippines, where they do not have to pay workers as much

money. The families of the first people who came from the U.S mainland own the important

banks and companies .Japanese are also buying or starting business here.

1. The author wants to show that _____.

A. we should all go to Hawaii.

B. it is possible to learn to live together in peace.

C. it is not possible to live together in peace.

D. Hawaii is the only place where there is peace.

2.  A  lei is _____. 

A. group of flowers                      

B. bright flowered shirt  

C. way to say hello and goodbye            

D. necklace of flowers

3. _____ plays an important part in the development of Hawaii. 

A .Modern industry  

B. Agriculture  

C. The air line  

D. Tourist trade

4. A good title for this article might be_____. 

A. Hawaii, the Aloha State            

B. Living in Peace Together

C. The Flowers of Hawaii              

D. The Problems of Hawaii