Functions of Lymphatic System
The main functions of the lymphatic system are as follows:
- The main function of the lymphatic system is to collect and transport tissue fluids from the intercellular spaces in all the tissues of the body, back to the veins in the blood system.
- Lymph plays an important role in returning plasma proteins to the bloodstream.
- Digested fats are absorbed and then transported from the villi in the small intestine to the bloodstream via the lymph vessels.
- Lymphocytes are manufactured in the lymph nodes
- Antibodies manufactured in the lymph nodes assist the body to build up an effective immunity to infectious diseases.
- Lymph nodes play an important role in the defence mechanism of the body. They filter out micro-organisms (such as bacteria) and foreign substances such as toxins.
- Lymph transports large molecular compounds (such as enzymes and hormones) from their manufactured sites to the bloodstream.
Optional Video: Lymphatic System
Elephantiasis is a disease characterised by thickening of the skin and underlying tissues, especially in the legs and genitals. It occurs when the body becomes infected by parasitic infections, which target the lymphatic system.
An Ethiopian farmer affected by elephantiasis after being infected by a worm that settled in the lymphatic system thereby causing the disease.
A comparison of the cardiovascular and lymphatic systems
The table below provides a comparison of the cardiovascular and lymphatic systems.
|Cardiovascular System||Lymphatic System|
|Blood is responsible for collecting and distributing oxygen, nutrients and hormones to the tissues of entire body.||Lymph is responsible for collecting and removing waste products left behind in the tissues.|
|Blood flows in the arteries, capillaries, and veins.||Lymph flows in an open circuit from the tissues into lymphatic vessels.|
|Blood flows towards the heart and away from the heart.||Lymph flows in one direction only (towards the heart).|
|Blood is pumped by the heart to all parts of the body.||Lymph is not pumped. It passively flows from the tissues into the lymph capillaries.|
|Blood consists of the liquid plasma that transports the red and white blood cells and platelets.||Lymph that has been filtered and is ready to return to the cardiovascular system is a clear or milky white fluid.|
|Blood is visible and damage to blood vessels causes obvious signs such as bleeding or bruising.||Lymph is colourless or translucent and damage to the lymphatic system is difficult to detect until swelling occurs.|
|Blood is filtered by the kidneys.||Lymph is filtered by lymph nodes located throughout the body.|