27 The Lymphatic System Flashcards
What is the lymphatic system
One way system of dead ending vessels and lymph nodes that pushes a colourless fluid called lymph throu it
What are lymph nodes
Swellings in the lymph vessels
They help to fight infection in the body
What is tissue fluid?
Fluid and some small proteins that are forced out of the plasma in capillaries
Tissue Fluid surrounds alll cells of tje body
What is the difference between tissue fluid and plasma
Tissue fluid does not have RBCs or Platelets
Tissue fluid has smaller amounts of WBCs and proteins
What is the role of tissue fluid
Acts as an exchange medium, allows molecules to pass in/out of it
How much tissue fluid is produced per hour
1 LITRE
Where is tissue fluid returned back to? and why must it be returned
Returned to the blood to prevent swelling called oedema from developing in the tissues
Formation of Lymph Simple
1.Blood in arteries under high pressure-> fluid forced out of plasma (tissue fluid)
2.Fluid forced our of plasma surrounds every cell in body
3.90%Tissue fluid reenters the blood in capillaries
4.10% enters dead ending lymph vessels -> the fluid is now called lymph
Tissue fluid is drained away by 2 routes, what are they
90% drawn back into plasma in the capillaries near veins by osmosis
10% enters dead end tubes called lymph vessels.The fluid is now called lymph
How is lymph moved through the lymph vessels
Contraction of body muscles
How is lymph prevented from flowing backwards
Valves in the lymph vessels
Where does lymph rejoin the blood stream
Near the neck
