问题 选择题

终身保持造血功能的骨髓位于

A.骨膜

B.骨松质

C.骨髓腔

D.骨密质

答案

答案:B

题目分析:人体内的骨髓有两种,一种是红骨髓,另一种是黄骨髓,幼年时人的骨髓腔里是红骨髓,具有造血功能,成年后骨髓腔里的红骨髓转变成了黄骨髓失去造血功能,但当人体大量失血时,骨髓腔里的黄骨髓还可以转化为红骨髓,恢复造血的功能,在人的骨松质里有红骨髓,终生具有造血功能,可见骨髓腔中具有造血功能的结构是红骨髓。

单项选择题

I remember my math teacher Mr. Young very well. He stood out because the kids made fun of him. He was missing one of his fingers, and always pointed at students with his middle finger.

I was not very good at English and math. No matter how hard I tried, I just could not figure out why I did not understand what all the other kids found so easy to learn.

One day, I was told that if I got one more E on my report card, I would be taken to the" big prison for kids".

I tried really hard for weeks. I just couldn’t understand how to make different parts of members into whole things.

The day before report cards were to come out, I knew that Mr. Young would give me an E ,just like he always did.

I went to Mr. Young and told him that the orphanage was going to send me to the big prison if I got another E on my report card. He told me there was nothing he could do;it would be unfair to the other kids if he gave me a better grade than I had actually earned.

I smiled at him and said, "Mr. Young, do you know how the kids make fun of you because you’re missing your finger" He looked at me, moved his mouth to one side and said nothing.

"They shouldn’t do that to you because you can’t help having a finger, Mr. Young. Just like I can’t help not being able to learn numbers and stuff like that. "I said.

The next day, when I got my report card, I tucked it into one of my books. While on the school bus, I opened it : Geography, B+ ; Mechanical Drawing, C- ; English, D- ; History, C- ; Gym, B+ ; Art, C ; Math, D-.

That math grade was the most favorite one I ever received. Because I knew that someone in the world finally understood what it was like for me to be missing a finger inside my head.

Where may the boy live according to the passage().

A. In an orphanage.

B. In a big prison.

C. In the school dormitory.

D. In his home.

单项选择题