试题与答案

苏云金芽孢杆菌产生的毒蛋白能使螟虫死亡。研究人员将表达这种毒蛋白的抗螟虫基因转入非糯

题型:填空题

题目:

苏云金芽孢杆菌产生的毒蛋白能使螟虫死亡。研究人员将表达这种毒蛋白的抗螟虫基因转入非糯性抗稻瘟病水稻的核基因组中,培育出一批转基因抗螟水稻。请回答:

选用上述抗螟非糯性水稻与不抗螟糯性水稻杂交得到F1,从F1中选取一株进行自交得到F2,F2的结果如下表:

表现型 抗螟非糯性 抗螟糯性 不抗螟非糯性 不抗螟糯性
个体数 142 48 50 16
分析表中数据可知,控制这两对性状的基因位于______染色体上,所选F1植株的表现型为______。亲本中抗螟非糯性水稻可能的基因型最多有______种。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:C

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题型:阅读理解

Over the past 20 years, AIDS and war have claimed the parents of 2.4 million Ugandan children.When Alexis Hefley first visited the country,, in 1993, she saw the children’s sorrow, but the former Texas banker also spotted "a world of possibility".She watched as they danced for tourists to earn money, and she had a thought: If people in America could see them perform, they’d support them too.                   

The children’s passion and talent inspired Hefley to work with the kids at an orphanage(孤儿院)in Kampala, the capital city of Uganda, to organize a traveling dance troupe(团).The goals: to give the problems in Uganda a human face, to raise awareness and to raise money.

The first tour touched down at six American cities in 1994.Today, the 22-member troupe, known as the Spirit of Uganda, travels across America every two years.The young performers bring their energy and joy to audiences across the U.S.and help support hundreds of Ugandan orphans back home.Among the young dancers, some earn scholarships to attend the U.S.colleges, and then return to their country to help rebuild it.

Photojournalist Douglas Menuez first photographed the troupe in 2006 -?a project that led to his new book, Transcendent Spirit, from which these images are drawn.At each performance, the dancers’ faces show pure joy, quite an achievement given the hardships they’ve faced."They look to the future, not the past," explains Menuez."They embrace beauty and good in the world." As one dancer puts it, "People think we have lost our parents.We’ve had so many problems.But then they see us perform.They see our smiles.And they learn that life goes on."

小题1:What are the first two paragraphs mainly about?     

A.How miserable Ugandan orphans’ life is.

B.How the dance troupe was set up.

C.How the young dancers earned money.

D.How the orphans lost their parents.|小题2:What do we learn about the Spirit of Uganda?            

A.It was started by a journalist.

B.It travels across the U.S.annually.

C.It consists of two dozen performers.

D.Its dancers have chances to study in the U.S.小题3:In the eyes of Menuez, the young performers are_____. 

A.beautiful

B.talented

C.optimistic

D.humorous小题4:What might be the most suitable title for the passage?      

A.Ugandan orphans turn tragedy into dance

B.Transcendent Spirit: A close look at Uganda

C.AIDS and war are claiming people’s lives

D.Lots of people are helping Ugandan orphans

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