The human body contains two parallel vital systems: circulatory and lymphatic. The first performs the function of nourishing the body, while the second purifies it of harmful substances. Scientists claim that the human lymphatic system (LS) arose in the process of evolution from the circulatory system. It consists of lymphatic capillaries, blood vessels and organs such as thymus, spleen, lymph nodes, and performs the function of ensuring the outflow of fluids from tissues and cells of the body into the circulatory system. However, unlike the circulatory system, drugs it has no arteries and does not imply a vicious circle, so the answer to the question: closed or open lymphatic system is obvious.
The capillaries are interconnected, thereby forming a closed network that covers almost all human organs. They consist of endotolial cells without membranes. Lymphatic capillaries absorb the destroyed cells, including tumor cells.
Capillaries up to two millimeters in diameter merge with each other and form lymphatic vessels, which consist of valves, trunks and ducts. Most often, the vessels are located near the veins; they can both carry lymph from the skin (epifascial) and carry lymph from the muscles and joints (subfascial vessels). The lymph in the vessels is a clear liquid, similar in composition to plasma. Lymphatic vessels form six ducts, which, in turn, form two main trunks: the thoracic trunk and the right lymphatic.
Also, the human lymphatic system carries out the flow of lymph from the internal organs. On this way there are more than ten lymph nodes, which are called "regional". Lymph nodes serve as a biological filter of the human body: they produce lymphocytes that protect the body from various infections and microbes, thereby forming immunity. In the human body there are about one hundred and fifty groups of lymph nodes, the largest of which are located on the neck, in the armpits, on the knees and elbows, on the back of the head and in the groin.
The largest lymph node is considered to be the spleen. The organ that regulates the entire lymphatic system is the thymus located in the chest. So, blood cells that enter this organ are converted into lymphocytes, which can eliminate negative formations in the human body. In adulthood, these cells turn into adipose tissue.
It should be noted that the lymphatic system is open: the lymph moves in one direction - from the tissues of the body to the heart. With a violation of the process of its movement, a person may experience edema. Lymph supplies cells with oxygen and various nutrients.
It is important to know that normally the lymph nodes are not palpable. In the presence of infection or tumor, they can be enlarged, therefore it is recommended in such cases to seek the advice of a specialist.
You can talk about how the human lymphatic system functions after various diagnostic measures, such as palpation, ultrasound, tests, and tomography. Today, a large number of various diseases of the lymphatic system are found, so early diagnosis can help to make a diagnosis on time and begin appropriate treatment.
Thus, the human lymphatic system, along with the circulatory system, plays an important role in the functioning of the entire human body. Being a protective barrier against many infections and diseases, it promotes the entry of oxygen and nutrients into the human organs, as well as the removal of decay products and even cancer cells from it.