食物消化和吸收的主要器官是（ ）
A．口腔
B．胃
C．小肠
D．大肠
答案：C
题目分析：小肠很长，长约5～6m，小肠内具有肠液、胰液和胆汁等多种消化液；小肠内壁有环形皱襞，皱襞上有小肠绒毛，增大了消化和吸收的面积；小肠绒毛内有毛细血管和毛细淋巴管，绒毛壁、毛细血管壁、毛细淋巴管壁都是由一层上皮细胞构成的，有利于营养物质被吸收进入小肠内壁的毛细血管和毛细淋巴管中．这些特点是与小肠的消化和吸收功能相适应的．
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| Rudi Matt lived in a small village in the Swiss Alps in 1865. What he wanted most in the world was to climb the highest peak (峰) in the Alps. Rudi's mother and his uncle, Franz, a mountain guide, wanted him to stop 1 and start working in a hotel. Rudi would not 2 his dream and secretly got in touch with an English mountain climber 3 was planning to climb the highest peak. Franz was very angry when he found out what Rudi had done, but he finally agreed to let Rudi go if he went climbing, 4 . Franz also didn't want to see Emil Saxo, a guide from another village, got to the top 5 him. Rudi turned out to be a very good climber, 6 as they got close to the top, the Englishman got sick and could go no farther. Franz stayed behind to take care of him, but Saxo continued, wishing to be the 7 to the top. Rudi went after Saxo, hoping to beat him to the top. When they met, Saxo fought with Rudi and fell down by accident. Saxo was helpless and hurt. Rudi must 8 whether to carry Saxo back down to safety or to continue alone to the top. He decided Saxo's life was more 9 than his dream and helped him down. During that time, the English man and Franz 10 the climb, and finally they reached the top. Later, when they returned to the village, they told people that Rudi was the real conqueror (征服者) of the mountain. |
| ( )1. A. learning ( )2. A. try out ( )3. A. what ( )4. A. again ( )5. A. after ( )6. A. but ( )7. A. first ( )8. A. wonder ( )9. A. important ( )10. A. stopped | B. playing B. give up B. which B. too B. behind B. so B. second B. remember B. successful B. continued | C. climbing C. go over C. whom C. once C. before C. or C. third C. ask C. popular C. enjoyed | D. talking D. work out D. who D. instead D. over D. for D. last D. decide D. interesting D. finished |