问题 选择题

下列有关血浆、组织液和淋巴三者关系的描述中正确的是

A.

B.

C.

D.

答案

答案:A

题目分析:根据肺泡内的气体交换可知,肺泡内的氧会不断扩散到肺部毛细血管的血液中,使静脉血变成动脉血,而肺泡内又不断地补充外界空气,使氧浓度一直高于肺部毛细血管血液中氧的浓度,这样才能使氧源源不断地扩散到血液中,氧浓度最高的部位应是血浆,然后血浆中的红细胞将氧气进行运输到组织液内,组织液内的氧气最终运输到组织细胞内液,组织细胞内液产生的二氧化碳通过扩散作用进入血液中的血浆中,所以此题答案为A。

点评:此题有一定的难度,解答此题的关键是理解气体交换的原理是扩散作用。

单项选择题
单项选择题

There are many kinds of friends. Some are always (1) you, but don’t understand you. Some say only a few words to you, but understand you. Many people will step in your life, but only (2) friends leave footprints.

I shall always recall the autumn and the girl with the (3) . She will always bring back the friendship between us. I know she will always be my best friend.It was the golden season. I could see the yellow leaves (4) with the cool (5) . In such a season, I liked walking alone on the roads covered with leaves, (6) to the sound of them.Autumn is a (7) season and life is uninteresting. The free days always get me (8) . But one day, the sound of a violin (9) into my ears like a stream flowing in the mountains. I was so surprised that I jumped to see what it was. A young girl, standing in the wind, was (10) in playing her violin.

I had (11) seen her before. The music was so nice that I listened quietly. Lost in the music, I didn’t know that I had been (12) there for so long but my existence did not seem to disturb her.Leaves were still falling. Every day she played the violin at the comer of the building (13) I went downstairs to watch her performance. I was the only listener. The autumn seemed no longer lonely and life became (14) . (15) we didn’t know each other, I thought we were already good friends. I believe she also loved me.Autumn was nearly over. One day, when I was listening carefully, the sound suddenly (16) . To my astonishment, the girl came over to me.

"You must like music from the violin." she said."Yes. And you play very well. Why did you stop’." I asked.Suddenly, a (17) expression appeared on her face and I could feel something unusual."I came here to see my grandmother, but now I must leave. I once played very badly. It was your listening every day that (18) me. " she said."In fact, it was your playing (19) gave me a meaningful autumn," I answered, " Let’s be friends. "The girl smiled, and so did I. I never heard her play again in my life. I no longer went downstairs to listen to her. Only thick leaves were left behind. But I will always remember the fine figure of the girl. She is like a (20) —so short, so bright, like a shooting star giving off so much light that makes the autumn beautiful.

第(19)空应选择()

A.that 

B.which 

C.it 

D.who