Your Body's Best Defense Against Germs:  The Immune System

Every day, your body fights off infections, germs, bacteria, and parasites.  It is destroying these invaders, called pathogens, with the help of its number one defense:  the immune system.  The immune system's job is to keep your body healthy.  This requires many different parts of the body to work together against pathogens.  Here are the main components of your immune system:

Tonsils

Located in the back of your throat, the tonsils protect the entrance of your respiratory and digestive systems by destroying bacteria with the help of white blood cells.

Thymus Gland

Located underneath the middle of your breastbone and above your heart, the thymus gland stores white blood cells until they are mature, and then provides them with specific jobs.

Lymph Nodes

Small, bean-shaped  nodules on the lymphatic vessels, lymph nodes are located primarily in your armpits and groin regions.  They filter pathogens out of the lymphatic system.

Bone Marrow

Located inside your body's bones, it produces red and white blood cells.  Red blood cells carry oxygen to other cells and body parts, and remove carbon dioxide.  White blood cells look for and destroy pathogens.  The different types of white blood cells are phagocytes, B-cells and T-cells.

Spleen

The largest lymphoid organ in the lymphatic system, the spleen is located to the left of your stomach.  The spleen removes pathogens from the blood as it passes through.

Liver

Your body's largest internal organ, the liver contains white cells.  These cells destroy bacteria in the blood as it passes through the liver.  It also processes nutrients found in the blood and produces bile used in digestion.

Blood

Red and white cells travel throughout your body's blood vessels.  While white blood cells defend against pathogens, your red blood cells nourish your body.