reinitiate cell division, and in some cases, when provided with the appropriate nutrients and hormones, even regenerate whole plants 极性是细胞分化的前提 极性是指细胞(也可指器官和植株)内不同区域在形态结构和生理生化上存 在差异的现象。极性的建立会引发不均等分裂,使两个子细胞的大小和内含物不 等,由此引起分裂细胞的分化。例如:胚胎发生在初期就建立了轴向极性。受精 卵在第一次分裂前已经极化。受精卵顶端含有较浓的细胞质成分,而基端主要含 个大的中央液泡。第一次分裂产生的两个细胞朝着不同的方向进行分化 Cell Polarity is a prerequisite of cell differentiation Cell Polarity refers to spatial differences in the shape, structure, and function of cells. Polarity establishment cause asymmetric cell division, thus the two daughter cells have differences in size and cell content which leads to the differentiation of the daughter cells. For example: Axial polarity is established very early in embryogenesi The zygote becomes polarized before its first division. The apical end of the zygote is densely cytoplasmic, but the basal half of the cell contains a large central vacuole The first division of the zygote creates two cells that carry out differentiation toward different directions 细胞分化受环境条件诱导 光照、温度、营养、pH、离子和电势等环境条件都能影响细胞的分化。如 短日照处理,可诱导苍耳提前开花;低温处理,能使小麦通过春化而进入幼穗分 化;对作物多施氮肥,则能使其延迟开花。 Environmental factors induce cell differentiation Environmental factors including light, temperture, nutrition, pH, ion, and electric potential can influence cell differentiation. For example: short day treatment can induce early flowering of Siberia Cocklebur: Low temperature treatment promotes wheat to start spike differentiation through velenization; nitrogen fertilizer causes delayed blossom of crop 植物激素调节细胞分化 植物激素能诱导细胞的分化,IAA有诱导维管组织分化的作用。培养基中生 长素和细胞激动素的比例影响愈伤组织的分化。当细胞分裂素相对浓度高,当生 长素的相对浓度高时,则有利于根的形成,而抑制芽的分化;反之,IAA与CTK 的比值低时,则有利于芽的形成,而抑制根的分化 Plant hormones regulate cell differentiation Certain hormones can induce cell differentiation One of the iaa functions is to induce vascular tissue differentiation. Root or bud differentiation depends on the ratio of IAA and cytokinin. High IAA/CTK stimulates root differentiation, but inhibits bud differentiation: while low IAA/CTK stimulates bud differentiation: but inhibits root differentiation 组织培养 植物组织培养是指植物的离体器官、组织或细胞在人工控制的环境下培养发 育再生成完整植株的技术。植物组织培养的理论基础建立在植物细胞全能性的概 念上。植物细胞的全能性是指植物的每个细胞在一定的条件下可以分裂、分化产 生植物体的各种细胞,最终发育成完整的植株。组织培养的过程主要包括脱分化 和再分化。组织培养技术已经广泛地应用于科学研究和生产实践。 Tissue culture tissue from a plant are transferred to an artificial environment in which they calor Tissue culture is a method of biological research in which cells or fragmentsreinitiate cell division, and in some cases, when provided with the appropriate nutrients and hormones, even regenerate whole plants. 极性是细胞分化的前提 极性是指细胞(也可指器官和植株)内不同区域在形态结构和生理生化上存 在差异的现象。极性的建立会引发不均等分裂，使两个子细胞的大小和内含物不 等，由此引起分裂细胞的分化。例如:胚胎发生在初期就建立了轴向极性。受精 卵在第一次分裂前已经极化。受精卵顶端含有较浓的细胞质成分，而基端主要含 一个大的中央液泡。第一次分裂产生的两个细胞朝着不同的方向进行分化。 Cell Polarity is a prerequisite of cell differentiation Cell Polarity refers to spatial differences in the shape, structure, and function of cells. Polarity establishment cause asymmetric cell division, thus the two daughter cells have differences in size and cell content, which leads to the differentiation of the daughter cells. For example: Axial polarity is established very early in embryogenesis. The zygote becomes polarized before its first division. The apical end of the zygote is densely cytoplasmic, but the basal half of the cell contains a large central vacuole. The first division of the zygote creates two cells that carry out differentiation toward different directions. 细胞分化受环境条件诱导 光照、温度、营养、pH、离子和电势等环境条件都能影响细胞的分化。如 短日照处理，可诱导苍耳提前开花；低温处理，能使小麦通过春化而进入幼穗分 化；对作物多施氮肥，则能使其延迟开花。 Environmental factors induce cell differentiation Environmental factors including light, termperture, nutrition, pH, ion, and electric potential can influence cell differentiation. For example: short day treatment can induce early flowerling of Siberia Cocklebur；Low temperature treatment promotes wheat to start spike differentiation through velenization; nitrogen fertilizer causes delayed blossom of crops. 植物激素调节细胞分化 植物激素能诱导细胞的分化，IAA 有诱导维管组织分化的作用。培养基中生 长素和细胞激动素的比例影响愈伤组织的分化。当细胞分裂素相对浓度高，当生 长素的相对浓度高时，则有利于根的形成，而抑制芽的分化; 反之，IAA 与 CTK 的比值低时，则有利于芽的形成，而抑制根的分化。 Plant hormones regulate cell differentiation Certain hormones can induce cell differentiation. One of the IAA functions is to induce vascular tissue differentiation. Root or bud differentiation depends on the ratio of IAA and cytokinin. High IAA/CTK stimulates root differentiation, but inhibits bud differentiation; while low IAA/CTK stimulates bud differentiation; but inhibits root differentiation. 组织培养 植物组织培养是指植物的离体器官、组织或细胞在人工控制的环境下培养发 育再生成完整植株的技术。植物组织培养的理论基础建立在植物细胞全能性的概 念上。植物细胞的全能性是指植物的每个细胞在一定的条件下可以分裂、分化产 生植物体的各种细胞，最终发育成完整的植株。组织培养的过程主要包括脱分化 和再分化。组织培养技术已经广泛地应用于科学研究和生产实践。 Tissue culture Tissue culture is a method of biological research in which cells or fragments of tissue from a plant are transferred to an artificial environment in which they can