问题 选择题

请你观察图四,将鸡卵的结构和相应的功能用线连接起来,应选(   )

                      

a.卵壳                 ①为胚胎发育提供主要营养

b.卵黄                 ② 进行胚胎发育的部位
c.胚盘                 ③ 提供胚胎发育所需的氧气
d.气室                 ④ 起保护卵细胞的作用
A. a-④,b-①,c-②,d-③          B. a-③,b-①,c-④,d-②

B. a-②,b-③,c-①,d-④          D. a-④,b-①,c-③,d-②    

答案

A

题目分析:鸟卵的结构,由外向内依次是卵壳、卵壳膜、气室、系带、卵黄膜、卵黄、胚盘等,卵壳上有许多肉眼可见的气孔,有利于进行气体交换,雏鸟由胚盘发育而来,胚盘是由受精卵分裂发育而来,为卵黄表面中央一盘状小白点,是胚胎发育的部位,胚胎发育的营养是由卵黄提供,鸟卵生殖发育过程:受精卵→胚盘→雏鸡,未受精的卵,胚盘色浅而小,已受精的卵的胚盘色浓而略大,这是因为胚胎发育已经开始,卵黄是胚胎发育的主要营养物质来源,卵白为胚胎发育提供营养物质和水,系带主要是固定卵黄。

单项选择题
阅读理解

While staying with a family, I found their teenage son, David, aged 16, didn’t share his true feelings with his parents. If his parents were present when I asked him how he felt about things, he would look down or away or say something unrelated such as, "Today, I will go out. "or "Okay, I guess. "However, when we were alone he would open up and tell me how he felt. For example, while sitting at the dinner table, I asked him how he felt about his history class and the teacher. He thought for a moment but said nothing. I thought he was afraid to answer in front of his parents, so later I asked him again in private. He said, "On a scale (级别) of 0-10, it is a big fat zero. He is the most boring teacher I have ever had. "I asked him why he didn’t tell me this earlier. He said it was because his parents didn’t want to hear that. They just wanted to hear that everything was wonderful and they always told him to stop complaining.

This made me think a lot. My belief is that children are born with the desire to share feelings. I also believe they are born with perfect emotional honesty. Unfortunately, such valuable things are disappearing gradually. It really is a great loss, which I believe, will negatively affect both the children’s ability to know about themselves and their success in future relationships.

I see the situation as a missed opportunity, an opportunity for parents to get closer to their children, an opportunity to understand their children and to help them feel understood; however, communication gaps (分歧) have been made. Parents are more interested in "correcting" their children’s ways of expressing themselves than in getting to know their children.

70. We can know from the passage that _________.

A. David is not good at talking  B. David likes showing his true feelings in public

C. David hates his parents      D. David dislikes his history teacher

71. According to the author, children who don’t show their true feelings ____________.

A. won’t succeed in their future careers

B. will not have good relationship with their parents

C. won’t have clear ideas of themselves

D. will have no difficulty getting along with others

72. The author thinks that parents should ____________.

A. stop complaining about their children

B. try to understand their children’s true feelings

C. find more ways to communicate with their children

D. correct their children’s ways of communication