Lymphatic System - Unit 3 Flashcards
What is the Lymphatic System
A secondary circulatory system
A one way system
What do lymph vessels do
Lymph vessels collect any fluid surrounding capillaries and returning it back to blood
Describe the structure of the Lymphatic System
It consists of lymph nodes, lymph vessels, tonsils, spleen and thymus gland
State three organs in the Lymphatic system
Tonsils
Spleen
Thymus gland
What are lymph nodes
Swellings in the lymph vessels
Where are lymph nodes located
Theyy are located in clusters in tonsils, neck, spleen and groin
How do these Lymph Nodes fight infection
The nodes filter bacteria
They contain large amounts of lymphocytes
True / False are Lymphocytes WBC’s
True
Lymphocytes are WBC’s
Describe the formation of lymph fluid
Arteries contain blood that is at higher blood pressure than veins
Due to this rapid movement and high pressure often some fluid aswell as some proteins are forced out.
This fluid is called tissue fluid.
Tissue fluid surrounds body cells and helps in the exchange of useful substances
T/F tissue fluid is actually useful
Yes as it aids in the exchange of substances in and out of cells
If tissue fluid is useful then why remove it?
Due to the fact over a litre is produced every hour.
So as to avoid swelling the body is required to remove this tissue fluid
What is the difference between tissue fluid and plasma
Tissue fluid has no platelets, RBC’s or clotting proteins but plasma does
How is Tissue fluid removed
10% of tissue fluid enters the lymph vessels.
This is the lymph fluid
90% of tissue fluid goes back into plasma which is in the capillaries by osmosis.
This process is aided by the low pressure in veins
Name two ways lymph differs from blood
Lymph had high levels of lipids
Lymph doesn’t have RBC’s, Clotting proteins or platelets but blood does
What does lymph fluid contain
High lipids (i.e high fat levels)
Has proteins
Has WBC’s
How does lymph fluid move slowly through lymph vessels
Physical activity squeezes vessels
Muscular walls of vessels
Valves prevent backflow of lymph fluid
Why is it lymph vessels are the same as veins moving fluid
Because blood in veins is also under low pressure
What do valves ensure
Ensure backflow of blood is prevented
What are the two main Lymph Vessels and where are they located
Thoracic Duct (Located on the Left)
Right Lymphatic Duct (Right Shoulder)
What returns through these ducts
It is through these ducts that the fluid is returned to blood at the subclavian veins near collar bones
Give 3 Functions of the Lymphatic System
Absorption of fats from digestive system to the lacteal
Collects tissue fluid and returns it to the blood
Defends the body against infection by:
- Node filtering bacteria
- Storage and Maturing of lymphocytes
What are villi
Small folding’s in the small intestine
Give the functions of villi
Absorption of glucose, amino acids and vitamins into the blood stream
Give some adaptations of the villi
have numerous microvilli (increased surface area for absoprtion)
have a rich supply of blood to carry away products
villi are only one cell thick; this allows for more efficient absorption
Each villi has a lacteal to absorb fats
Villi in general increase surface area for absorption
What’s the process when villi muscle contracts
Peristalisis
What is the Lacteal
A lymphatic vessel which is in the small intestine
It contains lymph fluid
Allows for absorption of fats which is then transported via lymph in lymph vessels
