The lymphatic system, in addition to the circulatory system, is another type of circulation that we have in the body. Like the circulatory system, The lymphatic system carries substances throughout the body. However, the latter is not a closed system, but has its beginning in the tissues of the body.
Therefore, its journey begins in the tissues, then is transported through the lymphatic vessels and ends in the blood. thus creating a one-way path.
As we said before, the main function of the lymphatic system is to transport a liquid called lymph which comes from blood and which has a very similar composition to it. This system is therefore the second network for the transport of body fluids. The lymphatic system performs four basic functions:
- Maintains osmolar balance.
- It helps to form and activate the immune system.
- Take the kilo (high fat product) from the intestinal contents.
- It controls the concentration of proteins in the interstitium, the volume of the interstitial fluid and its pressure.
The lymphatic system consists of lymph, lymph vessels, lymph nodes, and lymph organs (primary and secondary).
the sap

Lymph is a clear, somewhat whitish liquid that flows through the lymphatic vessels. It is made up of white blood cells proteinfats and salts. It is transported from the tissues to the blood through the lymph vessels.
It occurs after excess fluid leaks from the blood capillaries in the interstitial or intercellular space. It is then collected by the lymphatic capillaries which drain into the lymphatic vessels until it empties into the subclavian veins.
There is no pump in the lymphatic system that drives the lymph, as is the case in the heart and circulatory system. In this case, being between the muscle tissue and when the body makes movements, lymphatic circulation is activated. Because of this, this circulation is much slower than blood.
lymph vessels
Lymphatic vessels are the tubes through which lymph circulates and are very similar to veins. Like the latter, they consist of connective tissue and valves in the walls that prevent the lymph from rising.
As the vessels penetrate the body’s tissues, they become smaller and thinner. until they become lymphatic capillaries.
When the vessels have already become capillaries, it is the time when the substances that cannot pass through the blood because they their size does not allow them to pass through the blood vessel wallgo to the lymphatic system to be transported.
The lymphatic capillaries are getting bigger and bigger. until they converge in two main trunks which are the right lymphatic duct which collects lymph from the upper body and the thoracic lymphatic duct which collects it from the left side. Finally, these ducts open into the superior vena cava and the left subclavian vein.
lymph nodes
Lymph nodes are small nodules found in clusters in various areas of the body such as the neck, armpits and groin. The functions of these ganglia are as follows:
- Filter the sap of foreign substances.
- Destroy foreign substances, which can be for example bacteria or cancer cells.
- It produces white blood cells such as lymphocytes, monocytes and plasma cells.
When there is a infection in the body, these nodes increase in size as they greatly increase the production of white blood cells to be able to deal with it. If, after a while, the size of the lymph node does not return to normal, or even increases in size, you should see a doctor to rule out possible lymphoma.
lymphoid organs

lymphoid organs They are essential to defend us from infections, since they are in charge of synthesizing the cells that attack us and defend us against external aggressions. There are two types:
- Primary lymphoid organsThese are the thymus and the bone marrow, which in turn is where lymphocytes mature. T lymphocytes mature in the thymus and B cells in the bone marrow, which also synthesizes red blood cells, white blood cells, and platelets. It is found inside the bones.
- Secondary lymphoid organs: are the lymph nodes, the spleen and the MALT. It is in them that foreign substances (antigens) are introduced and the specific immune response is initiated. MALT is mucosa-associated lymphoid tissue and is found in the gastrointestinal, respiratory, and genitourinary tracts.
Have you ever been offered a lymphatic massage? If so, next time they do, you will know in more detail how you can benefit from them, by improving your blood circulation.
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