试题与答案

赖氨酸是一种人和高等动物的必需氨基酸,在食品、医药和畜牧业上的需要量很大,工业上

题型:读图填空题

题目:

赖氨酸是一种人和高等动物的必需氨基酸,在食品、医药和畜牧业上的需要量很大,工业上经常用黄色短杆菌生产赖氨酸。请回答下列有关问题:

(1)下表为黄色短杆菌发酵的培养基配方。该培养基中的碳源是__________,生长因子是________。

(2)下图表示黄色短杆菌合成赖氨酸的途径。赖氨酸属于黄色短杆菌的___________产物。分析图中代谢途径,当赖氨酸和苏氨酸都积累过量时,就会抑制天冬氨酸激酶的活性,使细胞难以积累赖氨酸。这种调节方式属于__________,其特点是________。

(3)目前,科学家已经通过对黄色短杆菌进行人工诱变处理,选育出________ 菌种,从而解决了原菌种不能大量生产赖氨酸的问题。

(4)在生产实际中,常采用______法,以保证微生物能较长时间的高速生长和提高设备的利用率。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B

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题型:不定项选择

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关于未签订书面劳动合同期间支付二倍工资的仲裁请求,下列选项正确的是:

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B.劳动合同到期后应签订新的劳动合同,否则属于未与劳动者订立书面劳动合同的情形,故李某有权请求支付二倍工资 

C.李某的该项仲裁请求已经超过时效期间 

D.李某的该项仲裁请求没有超过时效期间

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题型:选择题

读图“珠江三角洲与长江三角洲地区国际直接投资和外贸额所占全国比重的变化图”,回答问题

小题1:以下叙述正确的是

A.2001年,长江三角洲地区国际直接投资额占全国的比重首次超过珠江三角洲地区

B.长江三角洲地区外贸额占全国的比重不断上升,并超过珠江三角洲地区

C.珠江三角洲地区外贸额占全国的比重从1993年起一直呈下降趋势

D.图中所示的变化与外商投资区位选择的变化有关小题2:20世纪90年代以来,对比长江三角洲地区,珠江三角洲具有的优势条件是

A.产业基础良好

B.毗邻港澳和东南亚地区

C.腹地范围广阔

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A.地形的阻隔 

B.水源不足

C.夏季气温高温多雨  

D.河流航运里程较短小题4:以下工业中,最有可能在20世纪60~90年代初从日本迁移到珠江三角洲地区的是

A.服装制造业

B.钢铁工业

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C.有利于发挥珠江三角洲自然资源丰富的优势

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A.外来投资

B.个体私营企业发展

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题型:问答题

Anna lived on the side of a valley (山谷). One winter, there was a very big flood, and a lot of houses down below Anna’s house were washed away. Anna’s house was high enough to escape the flood, so when the water had disappeared and the other houses were standing there with no roofs and walls and all covered with mud, her house was still quite all right. That year Anna’s was very lucky.

Her house was quite small and there were only two small bedrooms, her husband was dead when the children were very young, and she had four children, but Anna took in one of the families that had lost everything in the flood and she shared her home with them until it was possible for them to rebuild their house.

Anna’s friends were very puzzled (困惑) when they saw Anna do this. They could not understand why Anna wanted to give herself so much more work and trouble when she had already quite a lot of children to support. Life would be even harder when another family joined them.

"Well," Anna explained to her friends, "at the end of the First World War, a woman in the town where I then lived in Germany found herself very poor, because her husband had been killed in the war and she had a lot of children, as I have now. "

"The day before Christmas, this woman said to her children, ’We won’t have much for Christmas this year, so I am going to get only one gift for all of us and I am sure we will all be glad to have it. Now I’ll go and get it.’ She came back with a little girl who was even poorer than they, and who had no parents. ’Here is our gift,’ she said to her children. "

"The children were very excited and happy to get such a gift. They welcomed the little girl, and she grew up as their sister, I was just that Christmas gift. \

Was her house washed away in the big flood()

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