一、生物变异的种类例1人类镰刀形细胞贫血症发生的根本原因是() A.基因突变B.染色体结构变异C.基因重组D.染色体数目变异解析变异主要分为两类:可遗传的变异和不可遗传的变异。可遗传的变异是由遗传物质的变化引起的变异;不可遗传的变异是由环境引起的,遗传物质没有发生变化。可遗传的变异的来源主要有3个:基因重组、基因突变和染色体变异。 I. Types of biological variation Example 1 The root cause of human sickle cell anemia is () A. Gene mutation B. Chromosome structural variation C. Gene recombination D. Chromosome number variation Analysis mutations are mainly divided into two categories: heritable Variation and non-heritable variation. Heritable variations are those caused by changes in genetic material; non-heritable variations are caused by the environment, and genetic material does not change. There are three main sources of heritable mutations: genetic recombination, gene mutation, and chromosome variation.