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树木的基本单位是由细胞所构成,细胞核悬浮于细胞质中,被细胞壁所包裹。细胞质是制造细胞的物质仓库,核有引导细胞发育的遗传密码。这种基本结构能发育成各种各样的生长物。通过显微镜来观察,树木的根系,枝干,叶的细胞很不一样,每种细胞都与相类似的细胞相结合,相类似的细胞群组成组织,组织的联合,成为更复杂的集团,称为器官。树木的根系能固定树木的身躯,吸收水分和养料。根尖是根系中的重要组成部分,它虽然娇嫩,却能穿入土表的深处,遇硬物能改变方向,螺旋穿钻,依附土粒吸收水分和养料。随着时间推移,根尖不断产生根毛,长得粗壮以支持树木的稳定,逐渐地变吸收作用为输导作用。根尖在土壤中吸收元素有选择性,对某些元素能很快地吸入,对某些元素却能排斥或降低吸入的速度。植物之间还有化学战争,有些植物的根部能分泌一些物质,能抑制另一些植物的生长。
The basic unit of the tree is made of cells, which are suspended in the cytoplasm and are surrounded by the cell wall. The cytoplasm is the material repository for the cells that make up the genetic code that guides the development of the cell. This basic structure can develop into a variety of growth. Observed by the microscope, the roots of the trees, branches, leaves of the cells are very different, each cell with similar cells, similar to the formation of cell groups, organizations, become more complex group, Known as the organ. Roots of trees can fix the body of trees, absorbing moisture and nutrients. Root tip is an important part of the root system, although it is delicate, but can penetrate the depths of the earth’s surface, in the event of hard objects can change direction, spiral through the drill, attached to the soil to absorb moisture and nutrients. As time goes by, root tips produce root hairs that grow thick to support the stability of the trees, and gradually change the absorption effect as a guide. Apical absorption of elements in the soil selective, for some elements can be quickly inhaled, but for some elements can be excluded or reduce the rate of inhalation. There are chemical warfare between plants, some plant roots can secrete some substances that can inhibit the growth of other plants.