The Lymphatic System is very important. It helps with the
Cardiovascular system, and our immune systems. The Lymphatic System is made up
of two semi-independent parts. One is a network of lymphatic vessels. The
other part is various lymphoid tissues and organs all over the body. The
functions of the Lymphatic System transporting fluids that have escaped from the
blood vascular system, and the organs house phagocytic cells and lymphocytes.
Lymphatic vessels are an elaborate system of drainage vessles that
collect the excess protein-containing fluid and returns it to the bloodstream..
Once an interstitial fluid enters the lymphatics it is called lymph. The
lymphatic vessels form a one way system in which lymph flows only towards the
heart. This entire transport sytem starts in the lymph capillaries. These are
very commmon, usually occur in the places blood capillaries occur. Lymph
capillaries are not found in bone, teeth, bone marrow, and entire central
nervous system. Lymphatic capillaries are very permeable. The endothelial cells
that make up the walls of the capillaries are not tightly joined. Filament
anchor the endothelium cells so they can expand. Pathogens can spread through
the body through the lymphatic stream.
There are many cells in the lymphoid tissue. One type is lymphocytes,
which are reffered to often as T or B cells. Plasma cells are antibody-producing
offspring of B cells. Macrophages are phagocytes that help out with immunity.
Reticular cells are cells that form the lymphoid tissue stroma. Thes cells are
very important parts of the immune system.
The Lymphatic System also contains tissues. The tissue of the Lymphatic
System is reticular connective tissue. It hold the macrophages and changes the
number of lymphocytes. It is an important part of the immune system. The
Lymphoid tissue can be found in the follicles. Lymphoid organs are discrete and
encapsulated. The main lymphoid organs are the spleen, tonsils, thymus and
The lymph nodes are placed along the lymphatic vessels. Each node has a
fibrous capsule, a cortex, and a medulla. The lymph nodes circulate fluids.
The lymph enters the lymph nodes through afferent lymphatic vessels and exits
through the efferent vessels. (afferent=enter, efferent=exit)
Most lymphoid organs contain both macrophages and lymphocytes. The
spleen is a place for immune function, and it kills defective or aged red blood
cells and blood-borne pathogens. The spleen also stores platelets, products of
hemoglobin, and acts as hematopoietic sites in the fetus. The Thymus contains
hormones. It is mostly functional in youth. Peyers patches are on the tonsils,
intestional wall, lymphatic nodules of the appendix and nodules of the respitory
The many functions of the lymphatic system help the body to maintain
body homeostasis. Some of the functions are removing foreign matter, maintain
correct blood volume, and very important in immunity. I never really realized
that the lymphatic system had so many functions. It seems to be a very important
part of the body. The immunity part is very important.