Cyanobacteria and protozoa. Polarised light micrograph of four Vorticella sp. protozoa (translucent) attached to filamentous colonies of Anabaena sp. cyanobacteria (dark). Cyanobacteria are bacteria that obtain their energy through photosynthesis. Vorticella are sessile, meaning they attach to a surface and cannot move around on their own. When disturbed, they contract their stalk into a tight coil. This contraction is one of the fastest known actions in the animal kingdom. Magnification: x200, when printed 10 centimetres wide.