Fig. 4. (A) The contractile vacuole (CV) potential (filled squares), and the rate of fluid segregation in the CV complex (R_CVC; open circles) of Paramecium multimicronucleatum as a function of the time of re-exposure of the cells to their original hypotonic adaptation solution (4 mosmoll^-1; abscissa) after they had received a prior exposure to a hypertonic solution (124 mosmoll^-1) for 30 min. Values are means ± S.E.M. (N=5-9). (B) DS-1 labelling of the decorated spongiome, visualized in immunological fluorescence images. The number at the top of each picture corresponds to the time (min) when the picture was taken following re-exposure of the cell to the hypotonic solution. The control cell was adapted to the hypotonic solution. Scale bar, 20 µm.