Hydra feeds by

Hydra feeds by digesting its food extra-cellularly. This means that Hydra releases enzymes (special proteins) outside its body to break down the food it has caught into smaller pieces. These small pieces are then absorbed by Hydra's cells and used for energy and growth. Unlike animals that chew their food or plants that make their own food through photosynthesis, Hydra does not masticate its food or synthesize its own food chemically. Hydra also does not absorb food that has already been digested by other organisms or have a symbiotic association with other species to obtain food.