问题 选择题

在巴斯德曲颈瓶实验中,甲瓶瓶口上的玻璃管是竖直向上的,乙瓶瓶口上的玻璃管是拉长呈S型的曲颈,将两个烧瓶内的肉汤同时煮沸放凉后,观察肉汤的变化。本实验的实验变量是(   )

A.氧气

B.烧瓶瓶口

C.微生物

D.烧瓶的形状

答案

答案:C

题目分析:由题意可知,如图,将两个烧瓶内的肉汤同时煮沸放凉,即两瓶中都高温灭菌,甲瓶的瓶口是竖直向上的,因此空气中的微生物会通过竖直的瓶口进入甲瓶的肉汤中,使肉汤变质腐败,而乙瓶的瓶口是拉长呈S型的曲颈的,空气中的微生物就会被S型的曲颈阻挡住,微生物就不能进入乙瓶的肉汤中,肉汤保持新鲜,由上可知,甲乙两组的区别是甲组肉汤中有微生物,乙组的肉汤中无微生物,是一组对照实验,变量是有无微生物。

点评:此题是基础题,掌握对照实验的相关知识,分析图形作答,此题的关键点:变量是微生物的有无,不是瓶颈的曲直。

填空题



The Commission is expected to propose allowing people to choose which (36) they would come under, based on their (37) or their residency. But the proposal is set to (38) because of the very different laws on divorce that apply across the EU. The Commission wants to (39) problems over which law to apply when, for example, a married couple from one member state is resident in another member state or when the couple is of different ELI nationalities.
The (40) of member states are said to be (41) the idea and responded positively to a (42) which followed the (43) of a Commission Green Paper. With 15% of German divorces each year involving couples of different nationalities, the government of Berlin (44) see resolved the issue of which laws should apply.
But some member states are expected to resist the (45) which would involve allowing different divorce laws to be applied in their countries. For example, Malta does not allow divorce. The proposal would mean that although Maltese nationals could not divorce in Malta, a couple of different EU nationality (46) in Malta could apply to the Maltese court for a divorce under their country’s laws. Similarly in Ireland where the divorce law states a couple must have been separated for four years, establish that their marriage has broken down and be offered (47) a couple from Sweden could apply to an Irish court to allow them to divorce under Swedish law, where divorce can be (48) quickly. The Irish government’s submission to the Commission on the Green Paper stated: "reland is not in favor of allowing (49) to choose the applicable law, as this could be open to abuse ... such abuse would be likely to (50) most on divorce regimes, such as that of Ireland, which require a relatively long separation period."
Ireland, like the UK, however, is allowed to choose whether to "opt-in" to such a proposal under rules agreed in the Amsterdam treaty. Malta has no such (51) but could (52) the proposal in the Council of Ministers since (53) approval will be required. "It is going to lead to (54) said Geoffrey Shannon, Irish expert on the Commission on European Family Law, which examines the (55) of EU family law. The proposal would also mean that judges would have to be trained in the divorce law of all 25 member states.
The Commission is expected to propose allowing people to choose which (36) they would come under, based on their (37) or their residency. But the proposal is set to (38) because of the very different laws on divorce that apply across the EU. The Commission wants to (39) problems over which law to apply when, for example, a married couple from one member state is resident in another member state or when the couple is of different ELI nationalities.
The (40) of member states are said to be (41) the idea and responded positively to a (42) which followed the (43) of a Commission Green Paper. With 15% of German divorces each year involving couples of different nationalities, the government of Berlin (44) see resolved the issue of which laws should apply.
But some member states are expected to resist the (45) which would involve allowing different divorce laws to be applied in their countries. For example, Malta does not allow divorce. The proposal would mean that although Maltese nationals could not divorce in Malta, a couple of different EU nationality (46) in Malta could apply to the Maltese court for a divorce under their country’s laws. Similarly in Ireland where the divorce law states a couple must have been separated for four years, establish that their marriage has broken down and be offered (47) a couple from Sweden could apply to an Irish court to allow them to divorce under Swedish law, where divorce can be (48) quickly. The Irish government’s submission to the Commission on the Green Paper stated: "reland is not in favor of allowing (49) to choose the applicable law, as this could be open to abuse ... such abuse would be likely to (50) most on divorce regimes, such as that of Ireland, which require a relatively long separation period."
Ireland, like the UK, however, is allowed to choose whether to "opt-in" to such a proposal under rules agreed in the Amsterdam treaty. Malta has no such (51) but could (52) the proposal in the Council of Ministers since (53) approval will be required. "It is going to lead to (54) said Geoffrey Shannon, Irish expert on the Commission on European Family Law, which examines the (55) of EU family law. The proposal would also mean that judges would have to be trained in the divorce law of all 25 member states.

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