FAP is a disease of the gastrointestinal tract which refers to the stomach, small intestine, and, most particularly, the large intestine. Digestive tract .
Food passes through the gullet, or esophagus, into the stomach.
Its function is to convert water and minerals, or liquid waste, into a more solid form. It is a warehouse for stool before evacuation takes place through the external opening, or anus. This organ is NOT required for digestion which occurs in the stomach and small intestine. The large intestine may also be referred to as the large bowel. Large intestine and portion of small intestine.