Lysosomes fuse with the food vacuole, and the digestive enzymes that the lysosomes contain are released into the food vacuole. The organism contained in the food vacuole is first broken down into food particles. These food particles are then broken down to food molecules such as sugars, amino acids, and lipids. The food molecules then diffuse or are actively transported into the ground substance of the cytoplasm where the food is utilized. Digestion that occurs in food vacuoles within a cell's cytoplasm is called intracellular digestion.
Digestive waste is eliminated from the food vacuoles of collar cells by exocytosis.
Amoebocytes are the food distribution system of sponges. The sponge body is composed of two layers of cells. Collar cells form one layer, and epidermal cells for the other. These two layers are separated by a jelly-like material called mesoglea. Amoebocytes are present within the mesoglea.