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问题 问答题

将A物质25g、B物质5g混合加热，反应后的物质中A仍有10g，B已反应完，同时生成C物质11g，还有一种生成物D，则这个化学反应中，参加反应的各物质与生成的各物质间的质量比为A：B：C：D=______．如果A、B、C、D相对分子质量分别为30、20、

44、18，则在化学方程式中A、B、C、D四种物质的系数分别为______．反应方程式为______．

答案

由题意可知，（25g-10g）A和5克B反应能生成11克C，生成D的质量为：15克+5克-11克=9克，则A、B、C、D四种物质的质量比为：15：5：11：9；

设ABCD四种物质化学式之前的化学计量数分别是abcd，则有aA：bB：cC：dD=15：5：11：9，因A、B、C、D相对分子质量分别为30、20、44、18，

故30a：20b：44c：18d=15：5：11：9，则abcd的数值比是2：1：1：2，则该反应的化学方程式为：2A+B=C+2D

故答案为：15：5：11：9；2：1：1：2；2A+B=C+2D．

读图填空题

转基因抗病香蕉的培育过程如图所示。质粒上有PstⅠ、SmaⅠ、EcoRⅠ、ApaⅠ等四种限制酶切割位点。请回答：

(1)构建含抗病基因的表达载体A时，应选用限制酶________，对_________进行切割。

(2)培养板中的卡那霉素会抑制香蕉愈伤组织细胞的生长，欲利用该培养筛选已导入抗病基因的香蕉细胞，应使基因表达载体A中含有__________，作为标记基因。

(3)香蕉组织细胞具有__________，因此，可以利用组织培养技术将导入抗病基因的香蕉组织细胞培育成植株。图中①、②依次表示组织培养过程中香蕉组织细胞的__________。
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填空题


Health officials in western Siberia are to begin in slaughter of thousands of birds today after identifying Russia’s first outbreak of a bird flu strain that can be fatal in humans. Doctors in neighboring Kazakhstan have also (1) that a 19-year-old poultry worker (2) admitted to hospital with (3) of bird flu, only to be diagnosed (4) double pneumonia.
The H5N1 strain of avian (5) has killed 60 people (6) 2fib in Vietnam, Thailand, Cambodia and Indonesia, but has rarely been found in birds or humans (7) Asia.
Health officials (8) that HSN1 is infecting migrating birds, which could spread the (9) into Europe. Earlier this year China registered the first outbreak of H5N1 (10) wild birds, some of which (11) to breeding grounds in Siberia. These birds could come (12) contact with others flying to Europe and North America.
Russia’s (13) began in the Novosibirsk (14) , about 1,750 miles (15) of Moscow in the Asian part of Russia, early last month, but the veterinary service (16) the virus only last week. Valery Mikheyev, the chief sanitary doctor of Novosibirsk, said that teams had been (17) the (18) birds and supervising the slaughter in13 (19) villages. He said, "The state of (20) of the inhabitants of these areas gives (21) cause for alarm. Up to 6,000 people are being (22) per day.
The virus seems to have (23) only private farms that let (24) mix with wild birds. Further outbreaks were registered in the Omsk and Altai regions, but the strain had (25) to be determined, Russia’s Emergency Situations Ministry said.
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