A&P - Chapter 31 (Part 1) Flashcards
What are the functions of the lymphatic system? (3)
- Maintain fluid balance in the body
- Plays a role in immunity
- Fat absorption and transport
What are the 6 structures of the lymphatic system?
- Lymph
- Lymphatic vessels
- Lymph nodes
- Thymus
- Tonsils
- Spleen
What is the fluid called when it goes from cell to tissue?
Interstital fluid
- filters out of capillaries into tiny spaces between cells and tissues
What is lymph fluid?
Is excess if it was absorbed by tissue cells or reabsorbed by the blood before it flows out of the tissue, drains into the lymphatic capillaries
- considered dirty
Where does lymph go?
It is drained back into the venous blood and back to the heart
What do lymphatic vessels do?
They permit one way movement of lymph towards the heart
What do lymphatic vessels collect?
Excess interstital fluid (as lymph) and returns it to the blood stream via veins
What are 2 types of lymphatic veins?
- Lymphatic capillaries
2. Lymphatic ducts
Lymphatic capillaries
Microscopic, blind-ended tubes found in tissue spaces wherever blood capillaries
Blind-ended
Open at one end
Where are lymphatic capillaries not located? (4)
- Bone
- Teeth
- Bone marrow
- CNS
What are lymphatic capillaries called when they are in the intestinal wall?
Lacteals
What do lymphatic capillaries have more of compared to veins?
Valves
What do lymphatic capillaries contain?
Lymph nodes
What will determine if fluid will move into or out of the lymphatic capillaries?
Fluid pressure in interstitial fluid
What happens when fluid pressure is greater in interstidial fluid than lymphatic capillaries?
The doors/valves are pushed open and the fluid moves in
What happens when fluid pressure is greater in lymphatic capillaries than interstidial fluid?
The doors/valves are pushed shut and it prevents lymph from leaking backwards
How many lymphatic ducts are there?
2
What are the 2 lymphatic ducts?
- Right lymphatic duct
2. Thoracic duct
What does the right lymphatic duct do?
Drain lymph from the right upper extremity, right side of the head, neck and upper torso
- right subclavian vein
What is the largest lymphatic vessel?
Thoracic duct
What does the thoracic duct do?
Drains lymph from the rest of the body
- left subclavian vein
What is found along the course of the thoracic duct?
Cisterna chyli
Cisterna chyli
Storage area for lymph moving towards entering the venous system
What is the function of the lymphatic vessels?
They remove high molecular weight substances and even particulate matter from interstitial spaces
What do lacteals do?
They absorb fats and other nutrients from the small intestines
What does the circulation of lymph not have?
No pumps
What does the circulation of lymph relay on? (2)
- Breathing
2. Skeletal muscle contractions
What do lymph nodes do?
They filter lymph
Where are lymph nodes located?
In clusters along the pathway of lymphatic vessels where they converge to form larger trunks
What is the function of lymph nodes? (2)
- Defence mechanism
2. WBC formation
