Mechanical properties of the protoplasm of the sea urchin egg

摘要: Abstract 1. Mechanical properties of the protoplasm fertilized sea urchin egg were determined by magnetic particle method. 2. The mechanical are roughly represented a visco-elastic model consisting Voigt element and viscous connected in series. 3. There is sudden rise visco-elasticity at fertilization followed fall to lowest value about 4 min after fertilization. rises parallel development sperm aster peak 13 then falls until metaphase, which it cleavage amphiaster. 4. consistency most pronounced center or polar centers It diminishes as region approaches periphery aster. high cortical cell. 5. spindle higher than that surrounding metaphase anaphase. During telophase, decreases region, so this within dumb-bell stage cytokinesis. 6. bearing these results on cytological changes occur during previous work discussed.