If a protist was placed in distilled water, how would this effect the pulsing of the contractile vacuole?
The contractile vacuole will contract much more often. The distilled water is hypotonic for the cells of the protist. That means that the concentration of water outside the cell is greater than the concentration inside the cell and more water will diffuse into the cell than the amount of water that diffuses out. The contractile vacuole will have to expel water more often to keep the pressure down inside the cell.
