Lymphatic System Flashcards
It assists the cardiovascular system by transporting excess interstitial fluid through lymphatic vessels. Lymph is filtered and checked for foreign or pathologic material, such as cancer cells and bacteria. Lymphatic structures contain certain cells that can initiate an immune response to abnormal materials and perform other functions essential to homeostasis and survival.
Lymphatic System Function
They are lymphatic vessels which drain into larger lymphatic vessels and eventually the bloodstream. They absorb lipids and lipid-soluble vitamins that are unable to enter the bloodstream directly from the GI tract. They also pick up interstitial fluid. The lymph is also called chyle.
Lacteals
They house lymphocytes which are a type of white blood cell or leukocyte. They assist in these cells’ maturation, while others serve for lymphocyte replication. They are completely surrounded by a connective tissue matrix.
Lymphatic Organs
They are not surrounded by a connective tissue capsule and are ovoid clusters of lymphatic cells with some surround extracellular connective tissue matrix. They are usually small. They attack and filter antigens. Some of these can group together to form MALT.
Lymphatic Nodules
MALT
Mucosa-associated lymphatic tissue. They are large collections of lymphatic nodules and are located in the mucosal lining of the GI, respiratory, genital, and urinary tracts. The MALT detects antigens from the respective tracts and initiate an immune response.
They are collections of lymphatic nodules that are primarily in the ileum. They can be quite large and bulge into the gut lumen.
Peyer Patches
They are closed-ended tubes that are found among most blood capillary networks, except those in the red bone marrow and central nervous system. They are similar but slightly bigger that blood capillaries.
Lymphatic Capillaries
They resemble small veins, in that both contain three tunics and both have one-way valves.
Lymphatic vessels
It is located near the right clavicle and returns the lymph into the juncture of the right subclavian vein and the right internal jugular vein. It receives lymph from the lymphatic trunks that drain the right side of the head and neck, right upper limb, and right side of the thorax. It is the shorter of the lymphatic ducts
Right lymphatic duct
It is the largest lymph vessel, with the length of about 15-18 inches. It travels superiorly from the cisterna chyli and lies directly anterior to the vertebral bodies. It receives lymph from the rest of the body that the right lymphatic duct doesn’t get lymph from. It drains lymph into the left subclavian vein and the left internal jugular vein.
Thoracic Duct
It is at the base of the thoracic duct and anterior to the L2 vertebra. It is a round, saclike structure. It receives chyle from the small intestine.
Cisterna Chyli
They attack and destroy the antigen directly.
Cytotoxic T-lymphocytes
They produce soluble proteins called antibodies that bind to and immobilize the foreign or abnormal agent, thus damaging it or identifying it to the other elements of the immune system.
B-Lymphocytes
They are cells that remember the past antigen encounters and initiate an even faster and more powerful immune response should the same antigen appear again.
T-memory cells and B-memory cells
They are large clusters of lymphatic cells and extracellular matrix that are not completely surrounded by a connective tissue capsule.
Tonsils
They have invaginated outer edges that trap material and facilitate its identification by lymphocytes.
crypts
are in the posterior wall of the nasopharynx. When these tonsils enlarge they can reduce air flow through the nasopharynx when sleeping.
Pharyngeal tonsils/adenoids
tonsils which are in the posteriolateral of the oral cavity.
Palatine
tonsils which are along the posterior one-third of the tongue.
Lingual
It is a bilobed organ located in the anterior mediastinum behind he sternum. It is quite large in infants and young children and is almost non-functional in late adulthood. It is a site for T-lymphocyte maturation and differentiation.
Thymus
