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[答]基因是在染色体上占有一定位置的遗传单位,从分子水平来看,就是脱氧核糖核酸(DNA)分子的一个片段,储有遗传信息,可以准确复制,发生突变,还可通过控制蛋白质的合成,对生命活动和遗传产生影响。DNA(染色体中主要成分)是由含有不同硷基的4种脱氧核苷酸(为了方便,下文叙述,分别简称为A、T、C、G)结合而成的双螺旋链,遗传信息就储存在A、T、C、G的排列顺序之中。人体每个基因内的核苷酸数目多在1,000个以上,它的排列顺序就可有41,000种之多,而人体中包含数以百万计的基因,从而形成了生物界多样遗传性。正是这些众多的基因控制了机体的各种遗传性状和代谢等生命活动。当基因改变时便会引起人体结构和机能的改变。基因突变是指染色体中某一位点或DNA分子中核苷酸的改变。通常是基因内1个到几个核苷
[Answer] A gene is a genetic unit that occupies a certain position on the chromosome. From a molecular point of view, it is a fragment of a DNA molecule that stores genetic information, can be accurately reproduced, has mutations, and can also control proteins. The synthesis has an impact on life activities and genetics. DNA (the main component of a chromosome) is a double helix chain composed of 4 types of deoxynucleotides (for convenience, described below, abbreviated as A, T, C, and G, respectively) containing different sulfhydryl groups, and genetic information is stored. In the order of A, T, C, and G. The number of nucleotides in each gene of the human body is more than 1,000, and its order can be as many as 41,000, and the human body contains millions of genes, thus forming diverse genetics in the biological world. It is these numerous genes that control the body’s various genetic traits and metabolic and other life activities. When the gene changes, it will cause changes in the structure and function of the human body. A gene mutation is a change in a nucleotide in a chromosome or DNA molecule. Usually 1 to several nucleosides in the gene