What is Lymph? Describe its system formation and composition

Lymph means a network of tissues, organs and vessels that help to maintain the body's fluid balance and protect it from pathogens. The lymphatic system is an accessory to the circulatory system, which allows it to do its job. Lymph doesn't circulate; it is unidirectional. We will discuss this in detail in this essay.

Let us discuss the lymphatic system and the role of lymph in this blog.

Lymphatic system

The lymphatic system is also a type of fluid transportation system in our body. Lymph, Lymphatic capillaries, lymphatic vessels, and Lymph nodes are its components.

• Lymph:Tissue fluid is another name for Lymph; which is a fluid flows in lymphatic system. It is named as Tissue fluid because it is a variety of connecting tissues but remember; it is not a primary or basic tissue type of the body. Lymph can carry sugars, protein, fat, vitamins, minerals, salt, water, germs or toxins, damaged or abnormal cells, etc., whereas harmful objects get filtered out by lymph nodes.
• Lymphatic capillaries:Lymphatic capillaries are tiny, thin-walled micro-vessels. Lymphatic capillaries have a distinctive shape that allows Lymph to flow in but not out.
• Lymphatic Vessels:They are thin-walled, having valves that carry Lymph. They collect Lymph from tissues throughout the body and, unlike blood vessels, only carry fluid away from the tissues.
• Lymph Nodes:Lymph is get collected into these nodes. Foreign particles, microbes, and damaged cells are filtered out when it passes through these nodes. Lymphocytes are produced by lymph nodes to destroy these undesired guests. Hence, we can say Lymph nodes are important to provide protection from these trespassers. Lymph organs like tonsils, spleen and lymph nodes play a significant role in our body's immune system.

Formation of Lymph

Interstitial fluid is the fluid that flows in the pores between the tissues. These fluids nourish cells of the body and remove wastes from the body. When tiny lymph capillaries, which are located throughout the body, collect these interstitial fluids, the formation of Lymph happens. 9/10th of the fluid flows through blood capillaries from the arterial end of the tissues. And remaining enters into Lymph capillaries.

White blood cells, specifically Lymphocytes, wash away the infectious germs and are visible as a colourless fluid throughout our body. Lymph veins are the channel that carries Lymph to tissues and then returns them to Lymph nodes, enabling them to move out and throughout the body. Blood exchanges its content with tissue cells to provide nutrition and vital metabolites to the cells of a tissue and remove the waste products they make. The interstitial fluid is a mediator for this exchange, which does not occur directly. The interstitial fluid's composition varies continuously as a result of the blood and the cells around it adding and removing chemicals.

Lymph flow rate is increased by lymphagogue. Interstitial pressure and Arterial Pulsation are two factors that regulate the rate of Lymph flow. As tissue fluid is the main reason for Lymph formation, its rate of formation increases if there is any increase in tissue fluid. As there is no secret process involved, its formation is totally dependent on physical factors.

1. Pressure on capillary: Rate of lymph formation increases as there is an increase in capillary pressure which can be seen in venous obstruction.
2. Capillary wall's permeability: More tissue fluid is formed if the permeability increase. Following are the reasons that increase capillary permeability.

• Capillary permeability increases if there is an increase in temperature in a particular area.
• Peptone, histamine, crayfish, leech etc., cause a hazardous effect on the capillary wall and will result in an increase in permeability.
• If there is a decrease in oxygen supply will result in an increase in Lymph formation.

3. Change in Osmotic pressure: If colloidal osmotic pressure reduces.

4. Metabolic Activity:If there is an increase in metabolic activities of a particular organ, lymph formation in that area increases.

Composition of the lymph

Lymph plasma, lymph corpuscles and lymphoid organs are three major compositions of the lymph. Let's discuss them in detail:

• Lymph Plasma: The interstitial fluid that flows in is called Lymph. Its composition is like that of Plasma. It contains low phosphorous, high glucose concentration, low calcium content, few blood proteins, water, organic and inorganic substances etc. It contains a group of proteins called Globulin, an antibody that plays a vital role in blood clotting, liver functions, and fighting infections inside the body.
• Lymph Corpuscles:In our blood or Lymph, small cells float, which are known as corpuscles. It's a mononuclear type of white blood cell formed in lymph nodes, blood and other lymphoid tissues. Leucocytes and amoeboid cells are part of it. They contain Lymphocytes which are specialized in involving in eliciting the immune system.
• Lymphoid Organs: Spleen, bone marrow, thymus and lymph tissues are the lymphoid organs in the human body. Thymus and bone marrow are primary, and MALT, spleen, and lymph nodes are the secondary lymphoid organs.

Functions of Lymphatic system

The main function of the Lymph are balancing fluid, absorption and many more. These are clearly mentioned in Class 12 biology. Let's list them here.

• Lymph moistens, lubricates and nourishes the body cells.
• Lymphatic vessels absorb fat from the small intestine and transport it to the liver.
• Antibodies and lymphocytes get transported to the blood through Lymph.
• Metabolic wastes get removed by Lymph and also play an essential role in transporting nutrients, hormones and oxygen to different parts of the body.
• Lymph maintains blood volume and composition of tissue fluid. The lymphatic system prevents water from clogging the tissues and cells by draining away excessive fluid.
• Lymphatic system has a vital role in the immune response of the body. It produces antibodies to fight bacteria.
• Lymphatic system maintains the functional and structural integrity of the tissue.
• Lymph channels absorb the end products of digestion.
• Protein and large size particulate matter are carried away from the tissue space by Lymph.

No place to confusion regarding blood and Lymph

There must be some confusion between Lymph and blood, but they are different. The Lymph is colourless, whereas the blood is reddish.Blood is part of the circulatory system, whereas Lymph fluid is of the Lymphatic system. Blood takes care of the transfer of oxygen and nutrients, whereas the Lymph's work is to help the immune system. Plasma is the main component of Lymph and blood, but the number of RBC, WBC and platelets are higher in blood than in Lymph. In Lymph, RBC and Platelets are absent. The Lymph is unidirectional and follows the direction from tissues to the heart, whereas blood flows in both directions towards and away from the heart.

Hope this blog will make a clear understanding regarding Lymph. Our qualified tutors will guide you if you want a specialized class to clear your doubts instantly. We have online tutoring services regarding Class 7 science, Class 8 science, Class 9 science, Class 10 science, Class 11 biology, and Class 12 biology, where you will get interactive and one-to-one sessions.