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| The lymphatic system. |
The lymphatic system is a complex network of lymphoid organs, lymph nodes, lymph ducts, lymphatic tissues, lymph capillaries and lymph vessels that produce and transport lymph fluid from tissues to the circulatory system. A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system. In human Anatomy, the thoracic duct (aka left lymphatic duct is an important part of the Lymphatic system &mdashit is the largest lymphatic vessel in the body Lymphatic Tissue is a specialized form of reticular connective tissue in the Lymphatic system that contains large numbers of lymphocytes Lymph capillaries or lymphatic capillaries are tiny thin-walled Blood vessels that are closed at one end and are located in the spaces between cells throughout the In Anatomy, lymph vessels are thin walled Valved structures that carry Lymph. Tissue is a cellular organizational level intermediate between cells and a complete organism This is an article about the rock music band "Circulatory System" The lymphatic system is a major part of the immune system. An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor
The lymphatic system has three interrelated functions: (1) removal of excess fluids from body tissues, (2) absorption of fatty acids and subsequent transport of fat, as chyle, to the circulatory system, and (3) production of immune cells such as lymphocytes (e. Chyle is a milky Fluid ( Bodily fluid) consisting of Lymph and emulsified Fats or free Fatty acids (FFAs A lymphocyte is a type of White blood cell in the Vertebrate Immune system. g. antibody producing plasma cells) and monocytes. Plasma cells (also called plasma B cells or plasmocytes) are cells of the Immune system that secrete large amounts of antibodies. Monocyte is a type of Leukocyte, part of the Human body 's Immune system. [1]
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Discovery
Olaus Rudbeck Sr. Olaus Rudbeck (also known as Olof Rudbeck the Elder, to distinguish him from his son and occasionally with the surname Latinized as Olaus Rudbeckius) (1630-1702 of Sweden (1630–1702) was a university dean, natural scientist, archaeologist and more. In 1652 he discovered the lymphatic system. He pointed to these as the source of production of white blood cells.
Lymphatic circulation
Unlike the cardiovascular system, the lymphatic system is not closed and has no central pump. Lymph movement occurs with low pressure due to peristalsis, valves, and the milking action of skeletal muscles. In the Esophagus After food is chewed into a bolus it is swallowed to move it into the esophagus Like veins, lymph travels through vessels in one way only, due to semilunar valves. In the Circulatory system, a vein is a Blood vessel that carries Blood back toward the Heart (as opposed to Artery, a blood vessel In Anatomy, the heart valves are Valves in the Heart that maintain the unidirectional flow of blood by opening and closing depending on the difference This depends mainly on the movement of skeletal muscles to squeeze fluid through them, especially near the joints. Rhythmic contraction of the vessel walls through movements may also help draw fluid into the smallest lymphatic vessels, capillaries. Capillaries are the smallest of a body's Blood vessels measuring 5-10 μm in diameter which connect Arterioles and Venules and enable the interchange Tight clothing can restrict this, thus reducing the removal of wastes and allowing them to accumulate. If tissue fluid builds up the tissue will swell; this is called edema. Oedema (or Edema in American English formerly known as dropsy or hydropsy, is the increase of Interstitial fluid in any organ &mdash swelling As the circular path through the body's system continues, the fluid is then transported to progressively larger lymphatic vessels culminating in the right lymphatic duct (for lymph from the right upper body) and the thoracic duct (for the rest of the body); both ducts drain into the circulatory system at the right and left subclavian veins. The right lymphatic duct, about 125 cm in length courses along the medial border of the Scalenus anterior at the root of the neck In human Anatomy, the thoracic duct (aka left lymphatic duct is an important part of the Lymphatic system &mdashit is the largest lymphatic vessel in the body In Human anatomy, the subclavian veins are two large Veins one on either side of the body The system collaborates with white blood cells in lymph nodes to protect the body from being infected by cancer cells, fungi, viruses or bacteria. This is known as a secondary circulatory system.
Function of the fatty acid transport system
Lymph vessels called lacteals are present in the lining of the gastrointestinal tract, predominantly in the small intestine. In Anatomy, lymph vessels are thin walled Valved structures that carry Lymph. A lacteal is a lymphatic capillary that absorbs dietary fats in the villi of the Small intestine. While most other nutrients absorbed by the small intestine are passed on to the portal venous system to drain, via the portal vein, into the liver for processing, fats (lipids) are passed on to the lymphatic system, to be transported to the blood circulation via the thoracic duct. In Biology the small Intestine is the part of the Gastrointestinal tract (gut between the Stomach and the Large intestine, and comprises The liver is a vital organ in the human body and is present in Vertebrates and some other animals In human Anatomy, the thoracic duct (aka left lymphatic duct is an important part of the Lymphatic system &mdashit is the largest lymphatic vessel in the body The enriched lymph originating in the lymphatics of the small intestine is called chyle. In Biology the small Intestine is the part of the Gastrointestinal tract (gut between the Stomach and the Large intestine, and comprises Chyle is a milky Fluid ( Bodily fluid) consisting of Lymph and emulsified Fats or free Fatty acids (FFAs As the blood circulates, fluid leaks out into the body tissues. This fluid is important because it carries food to the cells and waste back to the bloodstream. The nutrients that are released to the circulatory system are processed by the liver, having passed through the systemic circulation. The liver is a vital organ in the human body and is present in Vertebrates and some other animals The lymph system is a one-way system, transporting interstitial fluid back to blood.
Pathology
In elephantiasis, infection of the lymphatic vessels cause a thickening of the skin and enlargement of underlying tissues, especially in the legs and genitals. Elephantiasis (/ˌɛləfənˈtaɪəsɪs -fæn-/ -fan- is a disease that is characterized by the thickening of the skin and underlying tissues especially in the legs and genitals It is most commonly caused by a parasitic disease known as lymphatic filariasis. A parasitic disease is an Infectious disease caused or transmitted by a parasite. See special page for Filariasis in domestic animals Lymphatic Filariasis (Philariasis is a parasitic and
Lymphedema also causes abnormal swelling, especially in the appendages (though the face, neck, and abdomen can also be affected). Lymphedema, also spelled lymphoedema, also known as lymphatic obstruction, is a condition of localized Fluid retention caused by a compromised It occurs if the lymphatic system is damaged, or underdeveloped in some way. An estimated 170 million suffer with the disorder. There are three stages:
Stage 1: Pressing the swollen limb leaves a pit that takes a while to fill back in. Because there is little fibrosis (hardening) it is often reversible. Elevation reduces swelling.
Stage 2: Pressure does not leave a pit. Elevation does not help. If left untreated, the limb becomes fibrotic.
Stage 3: This stage of lymphedema is often called elephantiasis. It is generally only in the legs after lymphedema that has gone long untreated. While treatment can help a little, it is not reversible.
Some common causes of swollen lymph nodes include staph infections, infectious mononucleosis and neoplasm, e. Staphylococcus (in Greek σταφυλη staphyle means bunch of grapes and κοκκος coccos means granule is a genus of Gram-positive Infectious mononucleosis, also known as Pfeiffer's disease, mono (in The United States of America) and more commonly known as glandular g. Hodgkin's and non-Hodgkin's lymphoma, and metastasis of cancerous cells via the lymphatic system. The non-Hodgkin lymphomas are a diverse group of hematologic cancers which encompass any Lymphoma other than Hodgkin lymphoma. Metastasis ( Greek: displacement μετά=next + στάσις=placement, plural metastases) sometimes abbreviated mets,
Development of lymphatic tissues
Lymphatic tissues begin to develop by the end of the fifth week of embryonic life. Lymphatic vessels develop from lymph sacs that arise from developing veins, which are derived from mesoderm. One of the three Germ layers found in the Embryos of Animals more complex than Cnidarians making them Triploblastic.
The first lymph sacs to appear are the paired jugular lymph sacs at the junction of the internal jugular and subclavian veins. From the jugular lymph sacs, lymphatic capillary plexuses spread to the thorax, upper limbs, neck and head. Some of the plexuses enlarge and form lymphatic vessels in their respective regions. Each jugular lymph sac retains at least one connection with its jugular vein, the left one developing into the superior portion of the thoracic duct.
The next lymph sac to appear is the unpaired retroperitoneal lymph sac at the root of the mesentery of the intestine. It develops from the primitive vena cava and mesonephric veins. Capillary plexuses and lymphatic vessels spread form the retroperitoneal lymph sac to the abdominal viscera and diaphragm. The sac establishes connections with the cisterna chyli but loses its connections with neighboring veins.
The last of the lymph sacs, the paired posterior lymph sacs, develop from the iliac veins. The posterior lymph sacs produce capillary plexuses and lymphatic vessels of the abdominal wall, pelvic region, and lower limbs. The posterior lymph sacs join the cisterna chyli and lose their connections with adjacent veins. The cisterna chyli (or receptaculum chyli) is a dilated sac at the lower end of the Thoracic duct into which lymph from the Intestinal trunk and two
With the exception of the anterior part of the sac from which the cisterna chyli develops, all lymph sacs become invaded by mesenchymal cells and are converted into groups of lymph nodes. A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system.
The spleen develops from mesenchymal cells between layers of the dorsal mesentery of the stomach. The spleen is an organ found in all Vertebrate animals In humans the spleen is located in the abdomen of the body where it functions in the destruction of redundant Red The thymus arises as an outgrowth of the third pharyngeal pouch. In Human anatomy, the thymus is an organ located in the upper Anterior portion of the chest cavity just behind the Sternum.
See also
References
External links
- Lymphatic System
- Lymphatic System Overview (innerbody. Lymphangiogesis is the formation of lymphatic vessels from pre-existing lymphatic vessels in a method believed to be similar to Blood vessel development or Angiogenesis Lymphedema, also spelled lymphoedema, also known as lymphatic obstruction, is a condition of localized Fluid retention caused by a compromised Lymphoma a type of Neoplasm that originates in Lymphocytes (a type of White blood cell in the vertebrate Immune system) The American Society of Lymphology (ASL is a nonprofit group based in Kansas City, Missouri which deals with disorders of the Lymphatic system such as Lymphedema, also spelled lymphoedema, also known as lymphatic obstruction, is a condition of localized Fluid retention caused by a compromised com)
Dictionary
lymphatic system
-noun
- (anatomy) In mammals, including humans, a network of lymphatic vessels and lymph nodes that transport fluid, fats, proteins, and lymphocytes to the bloodstream as lymph, and remove microorganisms and other debris from tissues.
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