Anatomic structure and component of immune system
|Human Lymphatic System|
Human and animals have a self-defense system known as immune system. There are two types of immune system, innate immunity and adaptive immunity. Innate or non-specific immunityis the first barrier for all the invaders. The parts of body that functions as innate immunity are skin, tears, and saliva.
When the invaders succeed to come across the first barrier, the body will develop specific immune system that has been adapted called adaptive immunity. Adaptive immunity has four characteristics as follows.
- It only function when the invaders have come
- It is specific, meaning it only attacks specific invader,
- It has an ability to recognize and memorize even when the same situation occurs years later, and
- It generally will not attack the normal body’s components.
Human immune system involves several organs, such as lymphatic vessels, thymus glands, tonsil, bone marrow, spleen, liver, lungs, intestine, and lymph nodes.
The lymphatic vessels contain thick fluid consisting of white blood cells, such as lymphocyte and fat-containing fluid. Lymphatic vessels can be found in all organs, except brain, so that the lymphocyte can be taken, carried, and transferred to the certain parts of the body that need it.
Immune system organs are interconnected by lymphatic vessel tissues, so that it is called lymphatic system. The structure of lymphatic system comprises of lymph nodes and blood vessel-like lymphatic vessels. Immunity cells and foreign particles are carried by lymph fluid through this vessel. Lymph node are the organs where antigen is destroyed.