【摘要】 本文报道我国特有的一种绿藻门植物——泡状饶氏藻营养细胞的超微结构特征。植物体由3层细胞组成,外层细胞最小,细胞质比较丰富,含有较多的各种细胞器,液泡体积较小;中层细胞具有很大的中央液泡,细胞质成为贴壁的薄层,各种细胞器结构仍清晰可见;内层细胞极度液泡化,细胞质呈现退化状态。周生的片状叶绿体上有许多大小不等的穿孔,使叶绿体呈网孔状外貌。叶绿体主要由许多成对的类囊体组成,叶绿体上往往有几个蛋白核,蛋白核经常被1或2条类囊体穿过,呈现分隔状。本文也报道了泡状饶氏藻的线粒体、质体、内质网、高尔基体和核内微管的结构特征。根据泡状饶氏藻的类囊体形态与 Ulva mutabilis 非常相似以及蛋白核的超微结构特征,它与石莼科植物可能有较密切的亲缘关系,属于绿藻门中进化的类群。更多还原

【Abstract】 The present study reports the ultrastructural features of the vegetative cells in Jaoa bullata (Jao),Fan.,an endemic species of Chlorophyta in China.Its thallus is composed of 3 layers of cells.Outer cells are the smallest in size,containing abundant cytoplasm,rich in various organelles;their vacuoles are smaller.The cells of mid-layer possess a large central vacuole. Their cytoplasm becomes a thin layer appressed against the cell wall;Various kinds of the organelles are still clearly visible,Inner cells are extremely vacuolated.Their cytoplasm looks like degenerated. The cells are uninucleate,each containing a parietal,laminate chloroplast with numerous pores,which cause chloroplast a net-like appearance.The photosynthetic lamellae in a chloro- plast include a number of thylakoids mainly in pairs.Chloroplast contains several pyrenoids, which are penetrated by 1 or 2 thylakoids.The present study deals with the structural charate- ristics of the mitochondria,plastids,endoplasmic reticulum and dictyosomes in the cells of Jaoa bullata.Two groups of intranuclear microtubules are present in a cell. Based on the similarity to Ulva mutabilis in the thylakoid arrangement and the ultrastruc- tural features of the pyrenoids,authors suggest that Jaoa bullata(Jao)Fan may be closely related to Ulvaceae,among the advanced taxa in the evolution of Chlorophyta.更多还原