问题 选择题

正常人的尿液中,不含有下列何种物质(  )

A.大分子蛋白质

B.水

C.无机盐

D.尿素

答案

血液流经肾小球时,血液中除血细胞和大分子蛋白质外的尿酸、尿素、水、无机盐和葡萄糖等物质通过肾小球的过滤作用,过滤到肾小囊中,形成原尿.当原尿流经肾小管时,原尿中对人体有用的全部葡萄糖、大部分水和部分无机盐,被肾小管重新吸收,回到肾小管周围毛细血管的血液里.原尿经过肾小管的重吸收作用,剩下的水和无机盐、尿素和尿酸等就形成了尿液.所以,血浆、原尿和尿液的区别为:血浆和原尿的区别在于大分子的蛋白质;而原尿和尿液的区别在于葡萄糖.因此正常人的尿液中,不含有大分子蛋白质.

故选:A

改错题

第二节:短文改错(共10小题,每题1.5分,满分15分)

此题要求改正所给段文中的错误。对标有题号的每一行作出判断:如无错误,在该行右边横线上画出一个勾(√ );如有错误(每行只有一个错误),则按下列情况改正:

该行多一个词:把多余的词用斜线划掉,在该行右边横线上写出该词,并也用斜线划掉。

该行缺一个词;在缺词处加一个漏字符号(^ ),在该行右边横线上写出该加的词。

该行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。

My classmates and I worked as volunteer in Beijing                76.________

Paralympics in September 13 . Early in the morning at 7:20 ,            77.________

we gathered at the National Stadium , namely the Bird’s Nest.        78._______      

As soon as we got into it ten minutes late ,we started to do           79.________            

some cleaning . From 9:00 am to 4:00 pm , we tried our best help         80.________      

the disabled athletes to get ready for their competitions , leading the   81.________   

audience to their seats and keep order .It was until 12:00 that we      82.________ 

had lunch and took a rest ,which last about an hour . We stopped           83.________ 

working at 4:00 .Though it was a tired job , We felt                84.________   

that it an honor to serve the disabled friends from all over the world.  85.________

单项选择题