中英毕业论文翻译

转基因技术与传统技术的关系 自从人类耕种作物以来，我们的祖先就从未停止过作物的遗传改良。过去的几千年里农作物改良的方式主要是对自然突变产生的优良基因和重组体的选择和利用，通过随机和自然的方式来积累优良基因。遗传学创立后近百年的动植物育种则是采用人工杂交的方法，进行优良基因的重组和外源基因的导入而实现遗传改良。 因此，转基因技术与传统技术是一脉相承的，其本质都是通过获得优良基因进行遗传改良。但在基因转移的范围和效率上，转基因技术与传统育种技术有两点重要区别。第一，传统技术一般只能在生物种内个体间实现基因转移，而转基因技术所转移的基因则不受生物体间亲缘关系的限制。第二，传统的杂交和选择技术一般是在生物个体水平上进行，操作对象是整个基因组，所转移的是大量的基因，不可能准确地对某个基因进行操作和选择，对后代的表现预见性较差。而转基因技术所操作和转移的一般是经过明确定义的基因，功能清楚，后代表现可准确预期。因此，转基因技术是对传统技术的发展和补充。将两者紧密结合，可相得益彰，大大地提高动植物品种改良的效率。 下面分别对转基因动物和转基因植物来进行描述。Transgenic technology and the relationship between the traditional technology Ever since mankind has been cultivated crops, our ancestors would have never stopped the genetic improvement of crops. Over the past several thousand years the way crop improvement is mainly produced by natural mutation of genes and recombinant excellent selection and use, through the random and natural way to accumulate good genes. Genetics, nearly a hundred years after its founding breeding of plants and animals is the use of artificial hybridization method for the fine and exogenous recombinant genes into genetic improvement achieved. Thus, transgenic technology and conventional technology is the same strain, and its nature through genetic improvement of access to good genes. However, the scope and efficiency of gene transfer, the transgenic technology and conventional breeding techniques There are two important differences. First, the traditional techniques usually only between individuals within a species to achieve gene transfer, while the transgenic technology transfer genes between organisms is not kinship restrictions. Second, the conventional hybridization and selection techniques are generally carried out in the biological individual level, the operation targeted at the whole genome, the diversion of a large number of genes, some genes can not be precisely right to operate and selection, the performance of future generations predictable is poor. The transgenic technology operations and the transfer of a clear definition of the general is the result of gene, function well, and their offspring can accurately forecast the performance of. Thus, transgenic technology is the development of traditional technologies and additions. Closely integrate the two can complement each other greatly enhance the efficiency of plant and animal species improvement. The following were genetically modified animals and transgenic plants to be described.