Plasmalemma invaginations as characteristic constituents of plasmodia of Physarum polycephalum.

摘要: Plasmodia of Physarum polycephalum grown on agar or filter paper and fed with rolled oats as food a partially defined medium were morphologically analysed in the living state after fixation. Observation plasmodium growing reveals plasmalemma indentations outer regions protoplasmic strands, which studied more detail by phase-contrast microscopy unstained 1-µm sections. fixed embedded situ, i.e. close contact to their substrate, exhibit an extensive system invaginations characteristic constituents throughout all regions. In plasmodial strands measuring between 40 µm 1.5 mm diameter involved shuttle streaming, are found within ectoplasmic wall. Rounded-up parts this branched extracellular labyrinth limit endoplasmic core engaged mass transport protoplasm streaming. Despite clearcut borderline, central cortex connected occasional bridges. The phase can be interpreted either result from border strand, consequence pseudopodial-like processes originating extending into surrounding medium. invagination provides enlargement surface area multinucleate mass, probably important for absorption, excretion motility phenomena. thick diameters 0.2 mm, there is intimate connexion actomyosin fibrils system. attached and/or run parallel invaginated sheets. relations will described subsequent paper.