题干

无子西瓜的培育过程如下列简图表示:

根据上述图解,结合你学过的生物学知识,判断下列叙述错误是   (   )

A:秋水仙素处理二倍体西瓜幼苗,主要是抑制有丝分裂前期纺锤体的形成

B:四倍体植株所结的西瓜,果皮细胞内含有4个染色体组

C:无子西瓜既没有种皮,也没有胚

D:根据上述图解可知培育三倍体无子西瓜通常需要年年制种,但如果应用组织培养技术就可以快速进行无性繁殖

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C

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    Ideas about polite behavior are different from one culture to another. Some societies, such as America and Australia, for example, are mobile and very open. People here change jobs and move houses quite often. As a result, they have a lot of relationships that often last only a short time, and they need to get to know people quickly. So it's normal to have friendly conversations with people that they have just met, and you can talk about things that other cultures would regard as personal.

    On the other hand, there are more crowded and less mobile societies where long–term relationships are more important. A Malaysian or Mexican business person, for example, will want to get to know you very well before he or she feels happy to start business. But when you do get to know each other, the relationship becomes much deeper than it would in a mobile society.

    To Americans, both Europeans and Asians seem cool and formal at first. On the other hand, as a passenger from a less mobile society puts it, it's no fun spending several hours next to a stranger who wants to tell you all about his or her life and asks you all sorts of questions that you don't want to answer.

    Cross-cultural differences aren't just a problem for travelers, but also for the flights that carry them. All flights want to provide the best service, but ideas about good service are different from place to place. This can be seen most clearly in the way that problems are dealt with.

    Some societies have “universalist” cultures. These societies strongly respect rules, and they treat every person and situation in basically the same way.

     “Particularist” societies, on the other hand, also have rules, but they are less important than the society's unwritten ideas about what is right or wrong for a particular situation or a particular person. So the normal rules are changed to fit the needs of the situation or the importance of the person.

    This difference can cause problems. A traveler from a particularist society, India, is checking in for a flight in Germany, a country which has a universalist culture. The Indian traveler has too much luggage, but he explains that he has been away from home for a long time and the suitcases are full of presents for his family. He expects that the check–in official will understand his problem and will change the rules for him. The check–in official explains that if he was allowed to have too much luggage, it wouldn't be fair to the other passengers. But the traveler thinks this is unfair, because the other passengers don't have his problem.