Lymph node is a small organ of the lymphatic tissue. Lymph nodes can be found in armpit, stomach, groin, inguinal, neck, head and other parts of the body. Lymph nodes are linked by lymphatic vessels. Lymph nodes consist of a cortical (cortex) and the core (the medulla). Lymph nodes are located throughout the body, acting as a filter for foreign bodies and are very important for the immune system.
Lymph nodes are very important as they have clinical significance; for example lymph nodes in neck, head, or any other part of the body may get inflamed due to a certain medical condition like angina or may be the result of severe, life-threatening disease, such as cancer.
When inflamed or swollen lymph nodes will enlarge and will become hard and firm to feel. Read more about the lymphatic system.
Lymph nodes role and function
Pathogens (microorganisms that cause disease) can cause infection anywhere in the body. If a particular microorganism is present in the bloodstream, white blood cells will detect it. Contact of microorganisms with white blood cells occurs in lymphoid organs, which includes lymph nodes. During the infection lymph nodes may enlarge. In such cases we talk about the “swollen glands”. Swollen glands are an indicator that there is something wrong going on in a human body.
Lymph nodes structure
Lymph nodes are surrounded by a connective capsule, which passes into the lymph nodes and forming a strip (trabeculae), these are the columns of connective tissue, which is overgrown in the interior of the lymph nodes. Lymph node form the outer shell and inner core. The shell all around surrounds the core, except in the area where entering and leaving the veins – there medulla comes in direct contact with the surrounding tissue. Under the envelope so called wells are located, also known as subcapsular sinus.
The shape and size
Human lymph nodes are oval shape; in a normal state lymph nodes range from a few millimeters to 1-2 cm. In case of a tumor or infection lymph nodes may increase in size, mainly due to accelerated inflow of lymphocytes from the blood circulation. Sometimes lymph nodes remain enlarged after disease is gone.
How many lymph nodes does a human body consist of?
The human body consist of 500-600 lymph nodes; mainly in the armpits, groin, neck, chest and abdomen. Lymph nodes are a very important indicator of an overall health.
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