Paramecium caudatum ciliates from culture material. Focused on one individual, which shows pulsation cycles of the two contractile vacuoles. The contractile vacuoles act as osmotic regulators, controlling the influx of water across the ciliate's membrane by active expulsing the water out of the cell via the expulsing pores. Expulsion pores are located in the middle of the round-shaped contractile vacuoles and are easily visible with this magnification. Paramecia move by the rhythmic beating of many hair-like cilia, feed mainly on bacteria. These are digested within temporary digestive vacuoles which float within the cell cytoplasm. Capturing device: DSLR Canon 5DMk2 with Microscope adaption. Microscopic contrast method : Differential interference contrast. Captured field width : 0, 17 mm.