Lymph nodes are not the only lymphatic tissues in the body. The tonsils, spleen, and thymus gland are also lymphatic tissues. In the back of the mouth, there are tonsils. These produce lymphocytes, a type of white blood cell, and antibodies. They have a strategic position, hanging down from a ring forming the junction between the mouth and pharynx.
This enables them to protect against inhaled and swallowed foreign bodies. The tonsils are the tissues affected by tonsillitis. The spleen is not connected to the lymphatic system in the same way as lymph nodes, but it is lymphoid tissue. This means it plays a role in the production of white blood cells that form part of the immune system. Its other major role is to filter the blood to remove microbes and old and damaged red blood cells and platelets.
The thymus gland is a lymphatic organ and an endocrine gland that is found just behind the sternum. It secretes hormones and is crucial in the production, maturation, and differentiation of immune T cells.
Bone marrow is not lymphatic tissue, but it can be considered part of the lymphatic system because it is here that the B cell lymphocytes of the immune system mature. During gestation, the liver of a fetus is regarded as part of the lymphatic system as it plays a role in lymphocyte development.
Explore the model using your mouse pad or touchscreen to understand more about the lymphatic system. The lymph system has three main functions. The lymphatic system helps maintain fluid balance. It returns excess fluid and proteins from the tissues that cannot be returned through the blood vessels.
The fluid is found in tissue spaces and cavities, in the tiny spaces surrounding cells, known as the interstitial spaces. These are reached by the smallest blood and lymph capillaries. Around 90 percent of the plasma that reaches tissues from the arterial blood capillaries is returned by the venous capillaries and back along veins. The remaining 10 percent is drained back by the lymphatics. Each day, around liters is returned. This fluid includes proteins that are too large to be transported via the blood vessels.
Loss of the lymphatic system would be fatal within a day. Without the lymphatic system draining excess fluid, our tissues would swell, blood volume would be lost and pressure would increase. Most of the fats absorbed from the gastrointestinal tract are taken up in a part of the gut membrane in the small intestine that is specially adapted by the lymphatic system.
The lymphatic system has tiny lacteals in this part of the intestine that form part of the villi. These finger-like protruding structures are produced by the tiny folds in the absorptive surface of the gut. Lacteals absorb fats and fat-soluble vitamins to form a milky white fluid called chyle. This fluid contains lymph and emulsified fats, or free fatty acids. It delivers nutrients indirectly when it reaches the venous blood circulation. Blood capillaries take up other nutrients directly.
The third function is to defend the body against unwanted organisms. Without it, we would die very soon from an infection. Our bodies are constantly exposed to potentially hazardous micro-organisms, such as infections. However, pathogens often do succeed in entering the body despite these defenses. In this case, the lymphatic system enables our immune system to respond appropriately.
If the immune system is not able to fight off these micro-organisms, or pathogens, they can be harmful and even fatal. A number of different immune cells and special molecules work together to fight off the unwanted pathogens.
The lymphatic system produces white blood cells, known as lymphocytes. Some are as small as a pinhead, and others are about the size of a baked bean. The number of lymph nodes in the body differs from person to person.
Different parts of the body have different numbers of nodes. For example, there are about 15 to 30 small nodes in the armpit. The lymphatic system. On this page. What is the lymphatic system? The lymphatic system does different things: it acts as a one-way drainage system — this means it moves fluid from body tissues into the blood circulation it contains white blood cells called lymphocytes, which fight infection it gets rid of any waste that cells make.
How the lymphatic system works Lymph fluid normally flows through a network of lymph vessels. Lymph vessels, lymph fluid and lymph nodes Lymph vessels. Lymph fluid.
Lymph nodes. Print page. How we can help. If you need to talk, we'll listen. Share experiences, ask questions and talk to people who understand. Find out about support groups, where to get information and how to get involved with Macmillan where you live. Get help. Reviewed: 31 October Next review: 29 October Diseases and disorders of the lymphatic system are typically treated by immunologists. Vascular surgeons, dermatologists, oncologists and physiatrists also get involved in treatment of various lymphatic ailments.
There are also lymphedema therapists who specialize in the manual drainage of the lymphatic system. The most common diseases of the lymphatic system are enlargement of the lymph nodes also known as lymphadenopathy , swelling due to lymph node blockage also known as lymphedema and cancers involving the lymphatic system, according to Dr.
James Hamrick, chief of medical oncology and hematology at Kaiser Permanente in Atlanta. When bacteria are recognized in the lymph fluid, the lymph nodes make more infection-fighting white blood cells, which can cause swelling. The swollen nodes can sometimes be felt in the neck, underarms and groin, according to the NLM. Lymphadenopathy is usually caused by infection, inflammation, or cancer.
Infections that cause lymphadenopathy include bacterial infections such as strep throat, locally infected skin wounds, or viral infections such as mononucleosis or HIV infection, Hamrick stated.
In some areas of the body the enlarged lymph nodes are palpable, while others are to deep to feel and can be seen on CT scan or MRI. Inflammatory or autoimmune conditions occur when a person's immune system is active, and can result in enlargement of lymph nodes. This can happen in lupus, according to Hamrick.
This refers to cancer of the lymph nodes. It occurs when lymphocytes grow and multiply uncontrollably. There are a number of different types of lymphoma, according to Dr. Jeffrey P. Sharman , director of research at Willamette Valley Cancer Institute and medical director of hematology research for the U.
Oncology Network. Non-Hodgkin lymphoma is more common of the two, according to the Lymphoma Research Foundation. This most commonly occurs in women who have had surgery to remove a breast cancer.
Part of the operation to remove the breast cancer involves removing lymph nodes in the armpit. The more lymph nodes removed the higher the risk of chronic bothersome swelling and pain due to lymphedema in the arm, Hamrick explained.
Some interesting research has been done on why people possibly get lymphoma. From the research, they estimated that the risk of developing anaplastic large cell lymphoma in the breast after getting implants is 1 in 35, at age 50 , 1 in 12, at age 70, and 1 in 7, at age The study was published in the Jan.
This disease refers to a group of inflammatory disorders that cause lymph node enlargement and can result in multiple-organ dysfunction, according to the Castleman Disease Cooperative Network.
While not specifically a cancer, it is a similar to a lymphoma and is often treated with chemotherapy.
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