The lymphatic system is a system of thin tubes and lymph nodes that run throughout the body. These tubes are called lymph vessels or lymphatic vessels. The lymph system is an important part of our immune system. It plays a role in fighting bacteria and other infections and destroying old or abnormal cells
The lymphatic system is similar to the blood circulation. The lymph vessels branch through all parts of the body like the arteries and veins that carry blood. But the lymphatic system tubes are much finer and carry a colourless liquid called lymph. Lymph contains a high number of a type of white blood cells called lymphocytes that fight infection and destroy damaged or abnormal cells.
As the blood circulates around the body, fluid leaks out from the blood vessels into the body tissues. This fluid carries food to the cells and bathes the body tissues to form tissue fluid. The fluid then collects waste products, bacteria, and damaged cells. This fluid then drains into the lymph vessels.
The lymph then flows through the lymph vessels into the lymph node, which filter out any bacteria and damaged cells.
From the lymph nodes, the lymph moves into larger lymphatic vessels that join up. These eventually reach a very large lymph vessel at the base of the neck called the thoracic duct. The thoracic duct then empties the lymph back into the blood circulation.
The lymph nodes are small bean shaped structures, sometimes known as lymph glands.
There are lymph nodes in many parts of the body including
- Under your arms, in your armpits
- In each groin (at the top of your legs)
- In your neck
There are also lymph nodes that you cannot feel in your abdomen, pelvis and chest.
The lymph nodes filter the lymph fluid as it passes through them. White blood cells attack any bacteria or viruses they find in the lymph.