泡状饶氏藻营养细胞的超微结构研究

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。

ULTRASTRUCTURAL STUDIES OF VEGETATIVE CELLS ON JAOA BULLATA(JAO)FAN.

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.