Space flight effects on paramecium tetraurelia flown aboard Salyut 6 in the Cytos I and Cytos M experiments

Results of the Cytos M experiment and complementary results of the Cytos I experiment flown aboard the Soviet orbital station Salyut 6 are shown. Space flight of Paramecia cultures resulted in a stimulating effect on cell proliferation, in a larger cell volume, in changes in cell dry weight, cell total protein and the electrolyte content of the culture media in which the organisms were grown. The assumption of a possible effect of weightlessness on membrane permeability is discussed.