You have learned that dissolved materials always diffuse from where there is more of them to where there is less. Oxygen from the air dissolves in the moisture on the lining of the air sac and diffuses through the lining into the blood. Meanwhile, carbon dioxide diffuses from the blood into the air sac. The blood then flows from the lungs back to the heart, which sends it out to all other parts of the body.
Soon after air goes into an air sac, it gives up some of its oxygen and takes in some carbon dioxide from the blood. To keep diffusion going as it should, this carbon dioxide must be gotten rid of. Breathing, which is caused by movements of the chest, forces the used air out of the air sacs in your lungs and brings in fresh air. The breathing muscles are controlled automatically so that you breathe at the proper rate to keep your air sacs supplied with fresh air.
Ordinarily, you breathe about twenty-two times a minute. Of course, you breathe faster when you are exercising and slower when you are resting. Fresh air is brought into your lungs when you breathe in, or inhale, while used air is forced out of your lungs when you breathe out, or exhale.
26. In the respiratory process, only one of the following actions takes place: it is_______.
A. the diffusion of blood through capillary walls into air sacs
B. the diffusion of carbon dioxide through capillary and air sac walls into the blood
C. the diffusion of oxygen through the air sac and capillary walls into the blood
D. the exchange of nitrogen within air sacs
27. The number of times per minute that you breathe is_______.
A. independent of your rate of exercise
B. fixed at twenty-two times per minute
C. influenced by your age and sex
D. controlled automatically by an unspecified body mechanism
28. The process by which carbon dioxide and oxygen are transferred does not depend on
A. the presence of nitrogen in the blood
B. breathing muscles
C. the flow of blood
D. the moisture in the air sac linings
29. The authors style in this passage can best be described as---------.
A informal and matter of fact B. impersonal
C. personal P- matter of fact and formal
30. Which of the following words can replace the word exhale? A. Breathe out. B. Breathe in.
C. Diffuse. D. Exchange.
26. C 27. D 28. A 29. A 30. A
2014年职称英语卫生类完型填空练习十七
2014年职称英语卫生类完型填空练习十八
2014职称英语卫生类B级考前每日一练
卫生类英语完形填空(十二)
2014年职称英语卫生类完型填空练习十三
2014职称英语卫生类完型填空训练(八)
2014职称英语卫生类完型填空训练(一)
2014职称英语卫生B级练习:完形填空
2014年职称英语卫生类完型填空练习十六
2014职称英语卫生类完型填空训练(十四)
2014职称英语卫生类完型填空训练(十二)
2014职称英语考前每日一练(卫生类第43期-C级)
2014职称英语考前每日一练(卫生类第22期-B级)
2014年职称英语考试卫生类A级完型填空练习题(6)
2014年职称英语考试卫生类A级完型填空练习题(9)
2014年职称英语卫生类完型填空练习十二
2014职称英语考前每日一练(卫生类第17期-A级)
2014职称英语考前每日一练(卫生类第11期-B级)
2014职称英语考前每日一练(卫生类第5期-C级)
职称英语卫生类完型填空训练2
2014职称英语卫生类完型填空训练(七)
2014职称英语卫生完型新增文章-第7篇
2014职称英语卫生类完型填空训练(十一)
2014职称英语考前每日一练(卫生类第28期-A级)
2014职称英语卫生类完型填空训练(十)
2014职称英语卫生完型新增文章-第12篇
卫生类英语完形填空(十五)
职称英语卫生类完型填空训练8
2014年职称英语卫生类完型填空练习十五
2014职称英语考前每日一练(卫生类第37期-B级)
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |