Week 11: The Lymphatic System Flashcards
What is the lymphatic system?
A network of vessels, nodes and organs that work together to:
- maintain fluid balance
- support immune system
- facilitate absorption of fats
What are lymphatic vessels?
- thin walled vessels that parallel blood vessels
- transport lymph, a colourless fluid white blood cells, proteins, and cellular debris
What are lymph nodes?
Small, bean-shaped structures found along lymphatic vessels, which:
- filters blood
- removes damaged blood cells
- stores platelets
What are the lymphatic organs?
Spleen, thymus, tonsils
What is the function of the spleen?
- filters blood
- removes damaged blood cells
- stores platelets
- contains white pulp for immune growth
- located in upper left abdomen
What is the function of the thymus?
- critical for the development of T lymphocytes (T-cells)
- located in the upper chest
What is the function of the tonsils?
- defend against infections entering through the mouth and nose
- clusters of lymphatic tissue in the throat
What is lymph?
Fluid derived from interstitial fluid (fluid surrounding cells) and enters lymphatic vessels, which transports white blood cells and helps maintain fluid balance
What are lymphatic capillaries?
Microscopic vessels that collect excess interstitial fluid, and can be found in nearly all tissues
What are the main functions of the lymphatic system?
- fluid recovery
- immune response
- fat absorptions
- waste removal
How does the lymphatic system create fluid recovery?
Collects and returns excess interstitial fluid to the bloodstream
How does the lymphatic system aid immune response?
Lymph nodes and other lymphatic organs play a crucial role in immune surveillance, defence against infection and the production of immune cells
How does the lymphatic system aid fat absorption?
Lacteals (specialised lymphatic vessels) in the small intestine absorb dietary fats and fat-soluble vitamins, forming a milky fluid called chyle
How does the lymphatic system aid waste removal?
Removes cellular waste, debris and abnormal cells
Where does interstitial fluid move into?
Interstitial fluid is the fluid that surrounds cells, and enters lymphatic capillaries
What is the route of flow of lymph?
- Interstitial fluid enters lymphatic capillaries
- lymph transported through lymphatic vessels to larger vessels
- lymph passes through lymph nodes where filtration and immune response occur
- larger lymphatic vessels drain into the bloodstream, returning lymph to the circulatory system.
What are common lymphatic disorders?
- lymphedema
- lymphadenopathy
- Hodgkin’s lymphoma and non-hodgkin’s lymphoma
What is lymphedema?
Swelling due to the accumulation of lymph, often caused by a blockage or removal of lymph nodes
What is lymphadenopathy?
Enlargement of lymph nodes, often a response to infection
What is non/hodgkin’s lymphoma?
Cancers affecting lymphocytes
