Lymphatic System Flashcards
The lymphatic system
Made up of a series of vessels and organs. These vessels are separate to the arteries and veins.
Found throughout the body
anatomy and physiology
lymph Lymph vessels lymph nodes Lymph organs diffuse lymphoid tissue Bone marrow
bone marrow children v adults
Children have more bone marrow than adults.
what are the three functions of the lymphatic system
Draining excess interstitial fluid (fluid around the cells that make up a tissue)
transporting fats and fat soluble vitamins from the gastrointestinal tract
Immune response to destroy foreign cells and protect against disease.
draining excess interstitial fluid
approx. 21 litres of fluid from plasma escape into the tissues from the arterial end of capillaries daily. This becomes interstitial fluid.
This fluid bathes and surrounds cells and separates the cells from circulatory system.
helps bring oxygen and nutrients to cells and to remove waste products from them. As new tissue fluid is made it replaces older fluid which drains towards lymph vessels.
Transporting fats and fat soluble vitamins from the gastrointestinal tract
lymph vessels calls lacteals found in the villi of the GI tract. These lacteals remove fats and transport them to the blood stream. This mixture is called chyle. It is a milky white substance formed during digestion of fatty foods.
Chyle consists of a mix of lymphatic fluid and chylomicrons. Chylomicrons serve to transport fat from its port of entry in the intestine to the liver.
mounting an immune response to destroy foreign cels and protect against disease
Organs of the lymphatic system are involved in the production of lymphocytes
….
Functions of the lymphatic fluid…
immunological protection
Maintains fluid balance
absorbs fats
anatomy and physiology - lymphatic vessels
Similar to veins but have thinner walls
lymphatic capillaries are larger than blood capillaries
Lymphatic capillaries are open ended tubes constructed of overlapping endothelial cells. These cells separate when outside pressure exceeds that within the vessel. This allows fluid in but not out.
more valves than veins do
Movement of lymph is facilitated by muscular contraction
Lymph fluid
contains a high number of a type pf white blood cells called lymphocytes that fight infection and destroy damaged or abnormal cells.
No RBCs
lymph nodes
A lot concentrated around jaw line and neck and under the arm
filter lymph as it goes through
Lymph vessels drain into…
drain into two main trunks which empty into the venous system at the subclavian veins:
Right lymphatic duct
thoracic duct
Functions in relation to immunity
lymph nodes are termed secondary lymphoid tissues. This is where WBCs are activated.
what are the primary lymphatic organs
Where lymphocytes are formed and mature
Two primary: red bone marrow and thymus gland
What do the thymus and bone marrow do?
provide an environment for the stem cells (a cell that hasn’t yet differentiated into something) to divide and mature into T cells (in thymus) and B-cells (in bone marrow)
