题干

下列各国属于发展中国家的是(   )

A:英国

B:法国

C:加拿大

D:中国

上一题 下一题 0.0难度 选择题 更新时间:2015-07-03 05:19:22

答案(点此获取答案解析)

D

同类题1

材料分析题:
材料一:《达尔文的悲剧》
达尔文是19世纪伟大的生物学家,也是进化论的奠基人。然而在他还没有掌握大自然中生物界的奥秘之前,自己先受到了自然规律的无情惩罚。 1839年,30岁的达尔文与他的表妹爱玛结婚。爱玛是他舅舅的女儿。他们两人从小青梅竹马,感情深厚。但是,谁也没有料到,他们的6个孩子中竟然有3个夭亡。这件事情让达尔文百思不得其解,因为他和爱玛都是健康人,生理上没有什么缺陷,精神也非常正常,为什么生下的孩子却都是如此呢?达尔文到了晚年,在研究植物的生物进化过程时发现,异花传粉的个体比自花传粉的个体,结出的果实又大又多,而且自花传粉的个体非常容易被大自然淘汰。这时,达尔文才恍然大悟:大自然讨厌近亲结婚。达尔文意识到自己婚姻的悲剧在于近亲,所以他把这个深刻的教训写进了自己的论文。
材料二:
科学家将男、女体细胞内的染色体进行分析整理,形成了下面的排序图。

请分析材料回答下列问题:
⑴材料一中,从达尔文婚姻的悲剧可以看出,____ 是预防遗传病发生的有效措施。
⑵达尔文体细胞染色体的组成是材料二中的____  图。
⑶若材料二中的排序图表示的是电视剧《鲜花朵朵》中七个女儿父母的染色体组成,假如他们再生一胎,是男孩的可能性为____ 。
⑷正常人的染色体数目是相对恒定的,这对生命活动的正常进行非常重要。如果人的体细胞中多了或少了一条染色体,可能导致严重的____ 。

同类题2

任务型阅读

    Global Positioning System (GPS) is now a part of everyday driving in many countries. It is a space-based system that provides position and time information in all weather conditions. GPS can help people get to where they want to go.____When this happens, the driver is often to blame. Sometimes a GPS error is responsible. Most often, it is a combination of the two.

    ____Barry Brown, a GPS technologist, took an incident as an example. His friend once flew to an airport in the eastern United States. There he borrowed a GPS-equipped car to use. He wrongly plugged in the home address in the west. It wasn't until he was driving for thirty minutes that he realized it. Mr. Brown says this is a common human error. But he says, “One problem is that GPS has a very small screen and it can just tell you the next turn.____

    “The Normal and Natural Troubles of Driving with GPS” lists several areas where GPS can cause difficulties. They include maps that are outdated, incorrect or difficult to understand. ____GPS may fail due to these reasons and then lead to confusion for the drivers.

    Although GPS sometimes causes difficulties when people are driving, the most attractive point of this system is its 100% coverage on the planet. It is important for you to have to know what you are doing when you use GPS. You need to have the “ability” to be able to use GPS because it sometimes goes wrong.____

A. There are quite a few situations showing the problems of using GPS.

B. That means that it is not really telling you about going to the wrong place.

C. This space-based system is an important tool for civil and commercial users.

D. But sometimes it sends you to the wrong place or leaves you completely lost.

E. They also contain timing problems related to when GPS commands are given.

F. Advances in technology play an active role in modernizing GPS in many ways.

G. To make GPS well used, you need a good understanding of how drivers and GPS work.