Diagram of the Appendix

In the past, the appendix was considered an evolutionary leftover. Now however, scientists acknowledge that the appendix helps support the immune system in two ways. It helps tell lymphocytes where they need to go to fight an infection and it boosts the large intestine's immunity to a variety of foods and drugs. The latter helps keep your gastrointestinal tract from getting inflamed in response to certain food and medications you ingest.