Sea anemone

Anemomes have symbiotic relationships with either zooxanthellae, zoochlorellae or both which reside in the animals' gastrodermal cells. The sea anemone benefits from the products of the algae's photosynthesis, namely oxygen and food in the form of glycerol, glucose and alanine; the algae in turn are assured a reliable exposure to sunlight and protection from micro-feeders, which the sea anemones actively maintain. The algae also benefit by being protected due to the presence of stinging cells called nematocysts, reducing the likelihood of being eaten by herbivores.