The lymphatic system is the set of structures that allows draining
and the circulation of the lymph.
Lymph is a colorless or slightly yellowish liquid that plays a role in transport
Of certain nutrients such as lipids,
But also and especially in the immune system:
System responsible for the protection of the body!
The lymph, whose composition is close
Of the blood plasma.
It contains many lymphocytes,
A family of white blood cells, produced in
The bone marrow, which are responsible for defending the body against external aggressions starting with viruses and bacteria.
Thus, the lymphatic system comprises:
The vessels which circulate throughout the body the lymph and the lymphatic organs,such as the spleen, thymus, lymph nodes,or bone marrow, which produces white blood cells.
Lymph nodes are small, rounded organsscattered throughout the body.
They are located in the path of the circulation of the lymph, a biological fluidcontaining many cells involved in the defenseof the organism, especially leukocytes or white blood cells.
The main function of the lymph nodes is to ensure the cleansing of the
Lymph and promptly initiate defensereactions in the event of the arrival of external agents such as virusesor bacteria.
These lymph nodes are like small "storage-houses", small power stations located strategically on the path of the lymphatic vessels.
The lymphatic network is present throughout the body except for the central nervous system and non-vascularized tissues.
It is composed of two distinct circuits:
One for the upper right quarter of the body,
And one for the rest!
It begins with extremely thin capillaries,
The lymphatic capillaries, arranged in a network.
In the lymphatic capillaries follow the larger vessels, the lymphatic channels, or lymphatic trunks.
The lymphatic vessels are vessels organized in a system of very flat and sinuous channels, regularly relayed by ganglions.
These vessels have valves along their length, thus avoiding reflux.
However, unlike the veins, the lymphatic vessels are devoid of a muscular tunic and possess a one-way circulation.
Hence the interest of manual and postural drainage, to help the circulation!
The lymphatic ducts are joined together to form lymphatic vessels, which are more and more voluminous.
At the junction point of several channels
are the lymph nodes, which can be isolated or grouped into clusters in crossroads areas.
Especially at the root of the thigh and the axillary hollow!
The lymph is finally drained by two voluminous and terminal collectors.
The right lymphatic canal, 2cm long, drains the lymph of the upper right quarter of the body:
The right half of the head, neck and thorax
And the right upper limb.
It flows into the right subclavian vein at the base of the neck.
The thoracic duct; Measuring 40 cm, it collects the lymph of the rest of the body:
Lower limbs, pelvis, abdomen as well as the upper left quarter of the body.
It is born in the abdomen by a bulge, the chyle cistern, passes through the thorax,and throws itself at the base of the neckinto the left subclavian vein.
All the lymphatic pathways lead to the superior vena cava system by these two distinct circuits!
The chyle tank or chyle reservoir is a retro-aortic saccular lymphatic structure framed by the pillars of the diaphragme muscle.
It corresponds to a dilation of 2 to 3 cm, at the origin of the thoracic duct, opposite the second (L2) or the third lumbar vertebra( L3).
It drains all the lymph coming from all the subdiaphragmatic lymph nodes.
The lymphatic system combines two notions:
On the one hand, a one-way network of lymphatic vessels that originate in the body's various tissues to join the lymph nodes, which allow circulation and cleansing of the lymphe and to some extent the clearance of insoluble particles.
And on the other hand all the organs where there are large quantities of white blood cells...
Palatine tonsils, more commonly known as tonsils.
These two almond-shaped glands are the lymphatic organs of the throat,
Partly visible at the bottom of the mouth.
They play an essential role in immune defense because they are located at the pharynx at the entrance to the respiratory tract.
The thymus is a gland located in the upper Thorax, just behind the thorax and between the lungs.
It is part of the endocrine system and the lymphatic system.
Your thymus changes in size during your lifetime, and it begins to develop before birth.
In the newborn and young child, the thymus is voluminous in comparison to the size of the body.
The thymus develops during childhood until it reaches its maximum size, weighing about 40 grams at puberty!
After puberty, the tissue of the thymus begins to slowly shrink.
The activity of the thymus is then at its highest level in the child and the young.
In advanced adult age, most of the thymus is made of greasy tissue.
The thymus has two irregularly shaped sides,
Called lobes, each of which has three loyers:
The capsule, made of connective tissue and covers the outside of the thymus; The cortex forming the central layer; And the meula which is the inner layer.
The cortex and medula are made of a mixture of epithelial cells and lymphocytes that is a type of white blood cells.
Most lymphocytes are found in the cortex.
In the thymus, lymphocytes develop to become, at maturity, T cells(T means thymus).
The epithelial cells form a layer which covers the blood vessels and the connective tissue of the thymus.
They act by forming a barrier between lymphocytes and blood in the thymus.
This barrier prevents immature T cells from participating in an immune response until they become mature and leave the thymus.
Thus, the thymus is the lymphocyte school, where
They develop to become T- cells, once they are mature, they leave the establishment because of course, adults work and no longer go to school!
The spleen is located beneath the diaphragm;
it is a lymphatic organ which is placed against the anterior walls of the stomach on the left side of the abdominal cavity.
It is a soft organ located in the upper left part of the abdomen.
It is found approximately at the level of the 10th coast, which is called a splenic coast.
The spleen weighs on average 200gr,
Making it the largest of the lymphatic organs.
The spleen is richly irrigated by blood vessels,
On the other hand, it receives no lymphatic irrigation.
The spleen plays an essential role from an immune point of view.
Its role is to filter the blood and purify it.
It mainly works to destroy and recycle used red blood cells, so the iron will again be used for the production of hemoglobin.
Like the liver, the spleen also acts as a blood supply for the body.
Before birth, the spleen is the place of production of white blood cells, red blood cells and blood platelets.
The spleen only produces white blood cells.