The dead organic matter forms flacks in the sea, which slowly sinks to the bottom. This is called marine snow. The flakes serve as food for benthic animals, such as worms, brittle stars or sea potatoes. Organic matter also comes in a dissolved form. Bacteria consume dissolved organic matter and the flakes in the microbiological recycling. In turn, bacteria are consumed by ciliates (protists) and flagellates. Organic matter plays a key role in food chains and carbon cycles.