问题 选择题

心脏在血液循环过程中起着重要的作用,人们将它比喻为收集和排出血液的“泵”.如图中将血液“收集”回心脏的结构是(  )

A.5和6

B.7和8

C.6和7

D.5和8

答案

上下腔静脉回收的是全身各处器官里的血液,血液流入右心房,肺静脉回收的是肺部毛细血管里的血液,流入左心房.因此图中将血液“收集”回心脏的结构是⑤上下腔静脉、⑧肺静脉.

故选D.

填空题



For more than two centuries, American’s colleges and universities have been the backbone of the country’s progress. They have educated the technical, managerial, (1) and provided generation after generation of national leaders. Today educators from around the globe are turning to U. S. institutions of higher learning (2) . They are apt to find many reasons for the excellence of American universities, but (3) stand out as watersheds:
Education (4) : In 1862 Congress enacted the Land-Grant College Act, which essentially extended the opportunity of higher education (5) , including such disenfranchised groups as women and minorities. Each state was permitted to sell large tracts of (6) and use the proceeds to endow at least one public college.
(7) : Over the years, the decentralization and diversity of the America’s colleges and universities have promoted competition for students and resources. Competitive pressure first arose (8) . The academy’s impact really grew after World War II, when (9) commissioned by President Roosevelt argued that it was the federal government’s responsibility to (10) for basic research. Instead of being centralized in government laboratories, scientific research (11) in American universities and generated increasing investment. It also gave graduate students research opportunities and helped (12) far and wide, to the benefit of industry, medicine and society as a whole.
(13) : The end of the World War II saw passage of the Servicemen’s Readjustment Act of 1944. The law, which provided for (14) for returning veterans, made an already democratic higher-education system accessible in ways that were (15) in Europe, opening the doors of the best universities to men and women who had (16) of going to college.
(17) : The creation of federal loan guarantees and subsidy programs, as well as outright grants for college students brought (18) to higher education and further helped to democratize access. Since its founding (19) , the Federal Family Education Loan Program has funded more than 74 million student loans worth more than (20) .

单项选择题