下列有关毛细血管的叙述中，与物质交换不相适应的是（ ）
A．管内血流速度最慢的血管
B．红细胞呈单行通过的血管
C．连通最小动脉和静脉之间的血管
D．管壁是由一层上皮细胞构成
毛细血管是连接最小的动脉和最小的静脉之间的血管，其特点是：数量多，分布广，管壁薄，只有一层上皮细胞组成，管腔小，只允许红细胞呈单行通过，血流速度慢，这些特点有利于进行物质交换．
故选C
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| Why do I want to go to college? No one has ever asked me _1_ a question. But in my times I have asked myself. I have _2_ many ideas. _3_ important idea is that I want to be a better man. Many things make human beings different _4_ or better than or even superior (优越于) to animals. One of the most important thing is _5_. If I fail to receive higher education, my education _6_. As I want to be a fully _7_ man, I must get a well-rounded (全方位的) education, which good colleges and universities are supposed to _8_. I know one can get educated in many ways, but colleges and universities are _9_ the best places to teach me tow to educate myself. Only when I am well-educated, will I be a better man and _10_ serve the people. | ||||
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