Extracellular digestion is a process in which
saprobionts feed by secreting
enzymes through the
cell membrane onto the food. The enzymes catalyze the digestion of the food into
molecules small enough to be taken up by passive diffusion, transport or
phagocytosis . Since
digestion occurs outside the cell, it is said to be extracellular. It takes place either in the lumen of the digestive system, in a gastric cavity or other digestive organ, or completely outside the body.