题干

如图所示细胞中所含的染色体,下列叙述正确的是(  )

A:图a可能处于有丝分裂的后期,含有2个染色体组;图b含有3个染色体组

B:如果图b表示体细胞,则图b代表的生物一定是三倍体

C:如果图c代表由受精卵发育成的生物的体细胞,则该生物一定是二倍体

D:图d中含有1个染色体组,代表的生物一定是由卵细胞发育而成的,是单倍体

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C

同类题4

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    Renaissance is a French word. It means “rebirth”. It's a strange name for a period of history. What was exactly “ reborn” during the Renaissance?

    To answer this question, we need to look back at the time of the Roman Empire. At this time Roman artists, scientists and writers influenced by Greek ideas were the world's most advanced. They had become skilled observers of the natural world around them, and had become experts in studying animals, plants, the human body or the stars and planets. They wrote down their ideas about what they saw, and based their theories about the world on their observations.

    During the fourth and fifth centuries the Roman Empire slowly broke down. Many of the Romans' art and sculptures were destroyed and some manuscripts(原稿)were lost as well. But most importantly, some of the ancient attitudes were lost. A questioning approach to the world was replaced by an unquestioning one.

    Why did this happen? One reason was to do with the influence of the Christian Church. Through the thousand years following the fall of the Roman Empire, the Church controlled many aspects of life including education and learning. The Church ran all the universities and thought that the aim of a university should be to teach old ideas more clearly, not to introduce new ones. The scholars in the universities were expected to study God and heaven from the Bible and ancient books, rather than the world around them.

    Take medicine for example. The main textbook for doctors had been written by a Greek doctor called Galen more than a thousand years earlier. But when Roger Bacon, a thirteenth-century priest(牧师), said that a new approach to medicine was needed --- doctors should do their own original research instead of reading writers from the past such as Galen-the Church put him in prison.

    By the time of the fourteenth century, however, some parts of the Christian Church were becoming less strict about their ideas and there was a new state of mind among artists, doctors and scientist. People wanted to find out more about the world by studying it. This attitude of investigation had been common in classical scholars, and it was ‘reborn' during the Renaissance.