1, 2 & 10 Lymph nodes : The nodes filter out the damaged cells and cancer cells.
3. Tonsils and adenoids : The adenoids and tonsils work by trapping germs coming in through the mouth and nose.
4 & 11 Lymphatic vessels : Lymphatic vessels collect and filter lymph (at the nodes) as it continues to move toward larger vessels called collecting ducts.
5. Thymus : The thymus serves as the body's defense mechanism providing surveillance and protection against diverse pathogens, tumors, antigens and mediators of tissue damage.
6. Appendix : The appendix is designed to protect good bacteria in the gut.
7. Bone Marrow : It manufactures bone marrow stem cells and other substances, which in turn produce blood cells. Each type of blood cell made by the bone marrow has an important job.
8. Kidney : The kidneys act as very efficient filters for ridding the body of waste and toxic substances, and returning vitamins, amino acids, glucose, hormones and other vital substances into the bloodstream. The kidneys receive a high blood flow and this is filtered by very specialised blood vessels.
9. Preyer's patches : Peyer's patches play an important role in immune surveillance of materials within your digestive system. Immune surveillance refers to the process by which your immune system recognizes and destroys potential pathogens.