Golden algae, light micrograph

Differential interference contrast light micrograph of a golden algae Dinobryon sp. Golden algae are a large group of algae, found mostly in freshwater environments. In this colony individual cells, each cell is propelled by two flagella pulling the entire colony through the water in order to find good light. Dinobryon sp. is a mixotrophic organism, meaning that it is photosynthetic as well ashaving the ability to ingest food. When the light energy or nutrients are limited, it starts eating bacteria to survive. Each colony can eat thousands of bacteria every hour, providing as much as 50% of its energy requirements. Dinobryon is a potent force in controlling bacterial numbers in freshwater lakes and ponds. Magnification: x425 when printed at 10 centimetres wide at its longest edge., by HAKAN KVARNSTROM / SCIENCE PHOTO LIBRARY