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利用透射电镜技术研究了大车前(Plantago major L.)合子及其原胚发育特点。结果如下:大车前胚胎发育类型为柳叶菜类型。合子发育过程中,合点端的细胞壁逐渐形成,合子体积增大,极性增强,质体内贮藏淀粉。合子分裂通常发生在初生胚乳核分裂之后,第1次横分裂形成基细胞和顶细胞。基细胞经多次分裂形成单列细胞构成发达的胚柄;顶细胞多次分裂形成胚体,胚体细胞核大,核仁明显,细胞器的种类与数量多,呈现旺盛分生能力,具有很高的代谢活性。原胚发育过程中,小球胚初期,胚胎发育的营养物质主要来自合子储存的以及胚柄吸收并转运的营养物质;小球胚至中球胚期,胚柄组织迅速发育,依赖发达的胚柄自珠被组织吸收营养物质并转运至胚体;大球胚后期,胚柄开始解体,胚体外围细胞吸收胚乳的降解物作为胚胎发育所需营养物质。
Transmission electron microscopy was used to study the development of zygotes and their embryos in Plantago major L. The results are as follows: The type of prehoga embryo development is the type of willow leaf. During the development of zygotes, the cell wall of the conjunctival end gradually forms, and the volume of the zygote increases and the polarity is enhanced. Starch is stored in the plastids. Zygote division usually occurs after the division of primary endosperm nuclei, the first cross-division to form basal and apical cells. Basal cells divided into multiple cells to form a well-developed stem cells. The apical cells divide to form embryoid bodies. The embryoid bodies have large nuclei and obvious nucleoli. The types and numbers of organelles are abundant, Metabolic activity. In the process of embryo development, the nutrients of embryo development during embryogenesis mainly come from the storage of zygote and the nutrients that are absorbed and transported by embryo stems. The microstructure of hypocotyls from globus pallidum to midglobulin stage develops rapidly and depends on developed embryos Handle from the beads by the organization to absorb nutrients and transported to the embryoid body; large globular embryo, the embryos begin to disintegrate, the embryo body surrounding cells absorb endosperm degradation as embryonic development required nutrients.