(EDAPT WEEK 4)
Anatomy & Physiology III course with a lab
, Major Functions of the Lymphatic System
The lymphatic system is a multifaceted organ system with a great variety of
functionality including fluid balance, formation of lymph, lipid absorption and
transport, and immunity.
Fluid Balance
In a single day, about 30 L of fluid will leave the blood in the systemic capillaries
into the interstitial fluid. Of this 30 L, only about 27 L will return to the blood. As we
will see in the coming weeks, the amount of substances entering an area of the
body must equal what comes out, lest edema should occur. As such, lymphatic
capillaries will act to collect the remaining fluid in the form of lymph.
Formation of Lymph
This lymph will be composed of a mixture of water, ions, and various proteins. It is
the result of the filtration of blood plasma and the absorption of interstitial
fluids. This lymph will give the means of transport of pathogens to lymph nodes to
eliminate infection and can aid in the production of lymphocytes.
Lipid Absorption and Transport
Lacteals are lymphatic structures found within the lining of the small
intestine. These lacteals will absorb lipids and various other substances that we will
learn about in AP4. When the lipids enter the lacteals, they will pass through the
lymphatic vessels until they reach the veins. This lipid containing lymph is known
as chyle and will appear white.
Immunity
Foreign bodies such as pathogens and microorganisms will be filtered from the
lymph via lymph nodes and from the blood via the spleen. Lymphocytes that are
produced within the lymphatic system are capable of targeting and destroying
pathogens, preventing infection. When discussing many infectious diseases, it is
important to note that these diseases may produce symptoms associated with the
lymphatic system due to its role in fighting infection and filtering blood and lymph.
Review the following video for an overview of the Lymphatic System: