问题 读图填空题

酵母菌是生物科学研究中的重要生物之一,在高中生物学中涉及多个知识点,如图所示,请回答有关问题:

(1)在①中,酵母菌与大肠杆菌最大的不同点在于酵母菌具有________。

(2)酵母菌通过②和③的过程都能产生CO2,产生的场所分别是____和_____。

(3)在④课题研究中,用特定的培养液培养酵母菌,定时________,将培养液滴在______上,经处理后观察和计数,最后建立了酵母菌种群数量动态变化的_________。

(4)酵母菌在⑤中担任的角色是_________,能够将有机物分解成无机物。

(5)若选择酵母菌细胞中的质粒作为基因工程中的载体时,与目的基因之间形成重组质粒通常需要的工具酶有______________。

(6)在⑦过程中,不需要灭菌的原因是________________。

(7)酵母菌在⑧操作中,最关键的步骤是______________。

答案

(1)有成形的细胞核

(2)线粒体基质    细胞质基质

(3)取样   血球计数板   数学模型

(4)分解者

(5)限制性内切酶和DNA连接酶

(6)在缺氧且呈酸性的发酵液中,酵母菌能生存和繁殖,而绝大多数微生物都受到抑制

(7)配制海藻酸钠溶液

选择题
完形填空
完型填空

     Robert performs his 24-foot boat past willow(柳树) young trees that stick out of the waters of the
Mississippi River. __1__ dances off maples(枫树), their branches heavy with __2__ spring leaves. But a
 _3__ inspection discloses trouble behind the beautiful sight. Rubbish is __4__ in a logjam(浮木阻塞) and hangs from the tree's branches.
     For the next three hours Robert and his team pull plastic bags, tanks, bottles and __5__ bowling pins
out of the water. Then they __6__ for a picnic table caught in the trees. Welcome to the Mississippi River
Beautification Project begun in 1997 with Robert's one man __7__  to pick up rubbish __8__ a 400 mile
stretch(伸展) of the 2,340 mile river. That year, often working __9__, the 22-year-old fellow cleaned 150 miles of shoreline.
     At first the project appeared__10__ and useless. But Robert tried his best to find __11  , and with their backing, he soon had a new boat and five-man __12  -the Boom Crane Crew. Last year alone the crew
 __13_ from the water 44,055 gallon durms,1,104 tires and enough plastic bags to __14__  a football
field. Much of the waste will be __15__.
      "Robert's operation is the only one actually in __16___on the river," says Mark of the Mississippi
River Basin Alliance, a union of environmental groups. "It's the __17_I have ever seen in 20 years, and he
is inspiring others to do the __18_ ."
      "The river has given me a livelihood and brought me so much _19_ ," Robert says, "I want to do
something in __20_ ."

( )1. A. Sunlight  
( )2. A. ripe  
( )3. A. wider  
( )4. A. placed  
( )5. A. ever  
( )6. A. come  
( )7. A. work  
( )8. A. on    
( )9. A. alone  
( )10. A. large  
( )11. A. supporters
( )12. A. family  
( )13. A. came  
( )14. A. clean  
( )15. A. burned  
( )16. A. ending  
( )17. A. biggest  
( )18. A. deed  
( )19. A. time  
( )20. A. return  
B. Air  
B. brown  
B. quicker  
B. piled  
B. even  
B. save  
B. discovery  
B. in  
B. strongly  
B. happy  
B. workers  
B. team  
B. pulled  
B. cover  
B. buried  
B. progress  
B. earliest  
B. favor  
B. joy  
B. turn  
C. Water  
C. falling  
C. closer  
C. trapped  
C. nearly    
C. head    
C. place  
C. off     
C. quietly  
C. impossible  
C. engineers  
C. grade     
C. pushed    
C. build  
C. used    
C. discussion  
C. latest  
C. same    
C. pride  
C. pay  
D. Moonlight  
D. fresh      
D. stricter    
D. thrown      
D. merely      
D. fight      
D. effort      
D. along      
D. fiercely    
D. possible    
D. pioneers    
D. class      
D. appeared    
D. spread      
D. recycled    
D. common      
D. luckiest    
D. good        
D. waste      
D. trouble