生物学家将白鼠细胞的细胞核注入内部已抽空的黑鼠卵细胞内，激活后，移人棕鼠的子宫内发育，棕鼠最终产下了一只小鼠．这种生殖方式叫什么生殖？这只小鼠的体色是怎样的？为什么？
“克隆”的含义是无性繁殖，即由同一个祖先细胞分裂繁殖而形成的纯细胞系，该细胞系中每个细胞的基因彼此相同．通过题干可以看出：白鼠细胞的细胞核注入内部已抽空的黑鼠卵细胞内，激活后，移人棕鼠的子宫内发育，棕鼠最终产下了一只小鼠．用的是白鼠的细胞核，黑鼠的去核卵细胞，棕鼠的胚胎发育的场所（子宫）．因为细胞核是遗传信息库，含有遗传物质，能够传递遗传信息，所以，这种生殖方式叫克隆．该棕鼠生下的小鼠的体色是白色．因为白鼠提供了细胞核，细胞核是遗传信息库．②由上题可以看出：取的是黑鼠的胚胎细胞的细胞核，最终发育成的是小鼠的体色是黑色，所以，得出的结论是细胞核是遗传物信息的中心．
故答案为：克隆；白色；因为白鼠提供了细胞核，细胞核是遗传信息库．
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| When we visit another country, differences in music and dance are __1__ some of the first things that we notice.Every culture has __2__ its own types of music and dance, which are very different from those of other societies. Each type of music usually has a distinctive rhythm and a special sound, __3__ on the kinds of instruments that are used to produce it.The most common type of instruments are __4__ instruments, such as guitars and violins; wind instruments, including horns and flutes.Many different kinds of musical sounds __5__ be created by using different combinations of instruments. The human voice is a very special kind of instrument, __6__ it can produce a great number of different sounds with different __7__, ranging from loud to soft.Singing is very popular in most cultures because it allows us to __8__ words and ideas with music. Societies coordinate body movements with musical rhythms to create __9__.Sometimes people dance for fun and individual expression.Dances can also be used to __10__ ideas to an audience.Hawaiian dancers, __11__, use arm and hand movements to express the meaning of a song.In the same way, many societies use dances in religious ceremonies __12__ to tell about important events. Music and dance are passed from one __13__to another and thus become a permanent part of the society and __14__ culture.Of course, as cultures come __15__ contact with each other, the music and dance of one society may be accepted by other societies, or the different styles may be combined to __16__ a new kind of music or dance.Some Latin American music, for example, has taken __17__ from Indian cultures and mixed them with those from European and African cultures.__18__, popular music from England and the US can be heard in countries __19__ the world, __20__ it has had an influence on musical tastes, especially among young people. | ||||
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