the breaking down of food into simple substances occurs in the digestive system
rootage is system. breaking_down is bodily_function_event. digestive_system has mouth_and_salivary_glands digestive_system is system. digestive_system has do_with_food if metabolize occurs then digest occurs. digestive is substance. digestive_tract is organ_system. all_animals has digestive_system if digest occurs then consume occurs.