Digestion is exclusively intracellular in
Digestion is exclusively intracellular in protozoans (e.g., Amoeba) and sponges (e.g., Spongilla). Both intracellular and extracellular digestion occurs in cnidarians (e.g., Physalia) and mammals (e.g., Macaca). Digestion in annelids (e.g., Nereis) is extracellular.