某同学在做可溶性还原糖鉴定的实验中,进行了如下操作: 取一支试管,向试管内注入2

题型:问答题

问题:

某同学在做可溶性还原糖鉴定的实验中,进行了如下操作:

取一支试管,向试管内注入2mL苹果组织样液,向试管内注入2mL斐林试剂甲液(质量浓度为0.1g/mL的氢氧化钠溶液),再滴入4~5滴斐林试剂乙液(质量浓度为0.05g/mL的硫酸铜溶液),振荡试管,使溶液混合均匀,而后静止2min观察。请指出该同学的实验操作中存在哪些问题。

考点:实验:检测生物组织中的糖类、脂肪和蛋白质
题型:问答题

Tom walked into a shop . It had a sign outside : "Second-hand (旧的) clothes bought and sold . "He was carrying an old pair of trousers and asked the owner of the shop, "How much will you give me for these?" The man looked at them and then said: "Two dollars."

  "What !" said Tom. "I had guessed they were worth at least five dollars."

  "No," said the man, "they aren't worth a cent more than two dollars."

  "Well," said Tom, taking two dollars out of his pocket. "Here's your money. These trousers were hanging outside your shop. The list price (标价)of them was six dollars and a half. But I thought that was too much money, so I wanted to find out how much they were really worth."

  Then he walked out of the shop with the pair of trousers and disappeared before the shop owner could think of anything to say .

小题1:At first the owner of the shop thought that Tom __________.

A.wanted to steal the trousers   

B.wanted to sell the trousers

C.wanted to fool him      

D.wanted to buy the trousers小题2:The owner of the shop_______  for the old trousers.

A.would give Tom two dollars 

B.would pay three dollars

C.would pay five dollars      

D.would give Tom six dollars and a half小题3:The shop owner insisted(坚持) that the trousers were worth only two dollars because ____.

A.he wanted to sell them cheaply  

B.he wanted to buy them cheaply

C.he didn't like the trousers  

D.they were old and dirty小题4:In fact, the trousers _________.

A.were hanging inside the shop   

B.were stolen by Tom from the shop

C.had been the shop owner's    

D.had been Tom's小题5:From the story we know that _________ cheaper than the list price.

A.the owner sold the trousers two dollars

B.Tom sold the trousers one dollar and a half

C.the owner bought the trousers three dollars

D.Tom bought the trousers four dollars and a half

题型:问答题

《促进中部地区崛起规划》提出,中部地区铁路建设重点不包括()。

A.完善太原、郑州、武汉、长沙、南昌、合肥等枢纽站

B.强化晋煤东运、西运通道建设

C.建设长株潭城市群、中原城市群、武汉城市圈等城际客运系统

D.建设山西中南部铁路通道

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女性,55岁。巩膜及皮肤发黄9个月,伴皮肤瘙痒就诊。体检:巩膜及皮肤有明显黄染,肝脾明显肿大,考虑为原发性胆汁性肝硬化,下列哪项检查最有助于诊断?()

A.血清总胆红素、结合胆红素增高

B.尿三胆阳性

C.血清白蛋白与球蛋白比例倒置

D.血清线粒体抗体强阳性

E.血清IgG显著升高

题型:问答题

椎管麻醉时,哪种神经功能最先被阻断()

A.血管舒缩神经纤维

B.温度觉

C.深部感觉(本体感觉)

D.触觉

E.痛觉

题型:问答题

下列()药物在动物性食品中允许使用,不需要制定残留限量。

A.碳酸钙

B.阿维菌素

C.双甲脒

D.阿莫西林

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