问题 解答题

以下是人体部分生理活动示意图,请据图回答问题:

(1)A、B、C和D表示的是______的四个腔,血液从[C]______到[B]______的循环途径是______.

(2)在上图所示①~⑦的血管中流有动脉血的静脉是[______]______.

(3)a、b表示气体交换过程中的两种物质,a最终在______被利用.

(4)血管⑦内血液与⑥内血液相比,减少的成分主要是______.

(5)4表示某糖尿病病人小肠里的葡萄糖进入其血液的过程,是小肠的______过程;而此人的一部分葡萄糖最终又会通过人体的哪一途径排出体外?______(用图中序号表示).

答案

(1)心脏有四个腔:左心房、右心房、左心室、右心室,左心房连通肺静脉,右心房连通上下腔静脉,左心室连通主动脉,右心室连通肺动脉;血液在心脏和全部血管所组成的管道系统中的循环流动叫做血液循环,根据循环途径的不同,血液循环分为体循环和肺循环两部分;体循环是指血液由左心室进入主动脉,再流经全身的各级动脉、毛细血管网、各级静脉,最后汇集到上下腔静脉,流回到右心房的循环,肺循环是指血液由右心室流入肺动脉,流经肺部的毛细血管网,再由肺静脉流回左心房的循环.图示中A、B、C、D表示心脏的四个腔,血液从[C]右心室到[B]左心房的循环是肺循环.

(2)血液通过肺循环,从右心室射入肺动脉的静脉血,流经肺部毛细血管时,血液中的二氧化碳进入肺泡,肺泡中的氧气进入血液,这样,经过肺循环,流入肺静脉的是动脉血;即图示的血管中流动脉血的静脉血管是肺静脉.

(3)a是氧气,人体通过呼吸系统获得的氧气最终在组织细胞里参与氧化分解有机物,释放能量,供人体各项生命活动的需要.

(4)肾脏是形成尿的器官,血液流经肾脏后,经过肾小球的滤过作用和肾小管的重吸收作用,使血液中的部分含氮废物以尿液的形式排出体外,因此从肾脏中流出的血液中尿素等含氮废物会明显减少.图示中⑥是肾动脉,⑦是肾静脉,因此⑦内血液与⑥内血液相比,减少的成分主要是尿素等含氮废物.

(5)图示中,4表示营养物质透过消化道壁进入循环系统的过程,是小肠的吸收过程,糖尿病人体内的一部分葡萄糖随尿液排出体外,即通过图示中的2排出.

故答案为:(1)心脏;右心室;左心房;肺循环   

(2)⑤;肺静脉

(3)细胞

(4)尿素等含氮废物      

(5)吸收;2

阅读理解

About 21,000 young people in 17 American states do not attend classes in school buildings.

Instead, they receive their elementary and high school education by working at home on computers. The center for Education Reform says the United States has 67 public “cyberschools(网络学校)” and that is about twice as many as two years ago.

The money for students to go to a cyberschool comes from the governments of the states where they live. Some educators say cyberschools receive money that should support traditional public schools. They also say it is difficult to know if students are learning well.

Other educators praise this new form of education for letting students work at their own speed. These people say cyberschools help students who were unhappy or unsuccessful in traditional schools. They say learning at home by computer ends long bus rides for children who live far from school.

Whatever the judgment of cyberschools, they are getting more and more popular. For example, a new cyberschools called Commonwealth Connections Academy will take in students this fall. It will serve children in the state of Pennsylvania from ages five through thirteen.

Children get free equipment for their online education. This includes a computer, a printer, books and technical services. Parents and students talk with teachers by telephone or by sending emails through their computers when necessary.

Students at cyberschools usually do not know one another. But 56 such students finished studies at Western Pennsylvania Cyber Charter School recently met for the first time. They were guests of honor at their graduation.

小题1:What do we know from the text about students of a cyberschools?

A.They have to take long bus rides to school.

B.They study at home rather than in classrooms.

C.They receive money from traditional public schools.

D.They do well in traditional school programs.小题2:What is a problem with cyberschools?

A.Their equipment costs a lot of money.

B.They get little support from the state government.

C.It is hard to know students' progress in learning.

D.The students find it hard to make friends.小题3:Cyberschools are getting popular because__________.

A.they are less expensive for students

B.their students can work at their own speed

C.their graduates are more successful in society

D.they serve students in a wider age range

单项选择题 A1型题