问题
选择题
植物吸收水分的动力来自：
A．光合作用
B．蒸腾作用
C．受精作用
D．呼吸作用
答案
答案：B
题目分析：植物体通过根从土壤中吸收的水分， 90%以上的水都通过蒸腾作用以水蒸气的形式从叶片的气孔散发到大气中去了，这不是对水的浪费，蒸腾作用有其重要的意义，蒸腾作用是根吸水的动力，促使根从土壤中吸收水分，故选B。
搜题请搜索小程序“爱下问搜题”
植物吸收水分的动力来自：
A．光合作用
B．蒸腾作用
C．受精作用
D．呼吸作用
答案：B
题目分析：植物体通过根从土壤中吸收的水分， 90%以上的水都通过蒸腾作用以水蒸气的形式从叶片的气孔散发到大气中去了，这不是对水的浪费，蒸腾作用有其重要的意义，蒸腾作用是根吸水的动力，促使根从土壤中吸收水分，故选B。
| 完形填空。 | |||
| Jack Baines is a self-made millionaire, but his beginnings were very lowly. He was the youngest of eight children. His father had a 1 in a cotton mill(纱厂),but he was often 2 to work because of poor health. The family couldn't 3 to pay the rent or bills, and the children often went 4 . After leaving school at the age of 14, Jack was 5 what to do when Mr Walker, his old teacher, offered to lend him ~ 100 to start his own 6 . It was just after the war. Raw materials were not enough, and Jack saw a 7 in scrap metal (废弃金属). He bought bits of metal and stored it in an old garage. When he had built up a large amount, he sold it and 8 plenty of money. Jack 9 working hard. After one year he succeeded in 10 the ~ 100. By the time Jack was 30 years old he had 11 his first million, and he wanted to 12 this achievement by doing something " 13 ". With all his money it was 14 to build a beautiful home for himself and his parents. In 1959, " Baines Castle" was built in the 15 of the Lancashire countryside. It was one of the finest buildings in the country. Jack has recently sold "Baines Castle" for ~ 500 million, 16 Jack still can't get used to 17 the good life. He can often 18 drinking with the locals at the local pub(酒吧). "I remember being very 19 as a child, but never 20 as a child,"says Jack,"and I will never forget where I came from and who I am. " | |||
| ( )1. A. job ( )2. A. able ( )3. A. offer ( )4. A. wrong ( )5. A. seeing ( )6. A. school ( )7. A. problem ( )8. A. spent ( )9. A. enjoyed ( )10. A. developing ( )11. A. given ( )12. A. remember ( )13. A. common ( )14. A. impossible ( )15. A. ground ( )16. A. so ( )17. A. using ( )18. A. be found ( )19. A. rich ( )20. A. proud | B. work B. glad B. like B. hungry B. wondering B. farm B. purpose B. borrowed B. preferred B. saving B. made B. honour B. simple B. possible B. front B. and B. sparing B. find B. poor B. satisfied | C. company C. unable C. expect C. ill C. doubting C. business C. future C. wasted C. ptomised C. repaying C. taken C. celebrate C. interestin C. obvious C. spot C. or C. living C. look for C. healthy C. unhappy | D. house D. eager D. afford D. bad D. preparing D. store D. principle D. earned D. hated D. paying D. lost D. recognize D. grand D. basic D. heart D. but D. keeping D. be looked for D. well D. happy |