Introduction To Appendix : The appendix sits at the junction of the small intestine and large intestine. It’s a thin tube about four inches long. Normally, the appendix sits in the lower right abdomen. The function of the appendix is unknown. One theory is that the appendix acts as a storehouse for good bacteria, “rebooting” the digestive system after diarrheal illnesses. Other experts believe the appendix is just a useless remnant from our evolutionary past. Surgical removal of th e appendix causes no observable health problems. What Are the Symptoms of Appendicitis? The classic symptoms of appendicitis include: Dull pain near the navel or the upper abdomen that becomes sharp as it moves to the lower right abdomen. This is usually the first sign. Loss of appetite Nausea and/or vomiting soon after abdominal pain begins Abdominal swelling Fever of 99-102 degrees Fahrenheit Inability to pass gas Almost half the time, other symptoms of appendicitis appear, including: