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一、植物组织的概念植物组织是由许多相同的细胞互相联合而成,它们具有同一的来源,相同的形态,和相同的生理机能。因此植物组织不仅是一些细胞表面的结合,而更重要的是这些细胞间具有内部密切的联系。二、植物组织的种类构成植物体的组织种类很多,首先可分为分生组织和永久组织两大类:Ⅰ、分生组织:分生组织是植物一切组织的来源,它不断的分生促成了植物体的生长。一般分生组织细胞较小,排列紧密,无间隙,细胞壁薄,核大,细胞质浓厚,没有明显的液泡,此类细胞按其存在植物体中位置的不同又分为三类:A.顶端分生组织:位于植物根的末端和茎的顶端,往往集成一短小的圆锥体叫做生长锥,它的机能在于增生细胞,引长植物体,并分化成各种永久组织;这些组织都属于初生组织。B.居间分生组织:多见于禾本科植物,是节的上下两边和叶的基部所保留的分生组织,
First, the concept of plant tissue The plant tissue is composed of many identical cells, which have the same origin, the same morphology, and the same physiological function. Therefore, plant tissue is not only a combination of some cell surfaces, but more importantly, these cells have close internal connections. Second, the types of plant tissues constitute a lot of plant species, first of all can be divided into two major categories of meristems and permanent organizations: I, meristems: meristem is the source of all plant tissue, and its continuous division of life to promote The growth of the plant body. In general, the meristem cells are small, tightly packed, gap-free, with thin cell walls, large nucleus, and dense cytoplasm. There are no obvious vacuoles. These cells are divided into three categories based on their position in the plant body: A. Organisms: Located at the ends of plant roots and stems, they often incorporate a short cone called a growth cone. Its function lies in proliferating cells, leading into plant bodies, and is differentiated into various permanent tissues; these tissues belong to the primary tissue. . B. Intermediary meristems: More common in Gramineae plants, which are the meristems retained by the upper and lower sides of the festival and the base of the leaves.