Lymphatic System Flashcards
(11 cards)
1
Q
Functions of lymphatic system
A
- collect fluid that has escaped capillaries and return it to circulatory system
- plays a role in body’s internal defence against disease-causing organisms
2
Q
What might happen to blood in capillaries
A
- may leak bc of high pressure of arterial end
- most returned back in venous end
- rest need to be returned by lymph vessels
3
Q
Lymph vessel structure
4
A
- 1 cell thick
- 1 way system - away from tissue
- low pressure and valves prevent backflow
- slightly larger and more permeable than capillaries -> proteins & disease-causing ogranisms can easily pass through walls
4
Q
Movement of lymph
excess blood
A
- smooth muscle layer of vessels contract to push lymph
- skeletal muscle contracts for additional force
- larger lymph vessels have valves to close when pressure drops bc there is no central pump
5
Q
Where do lymph vessels end
A
join up to form 2 main lymph ducts to empy lymph in veins in upper chest
6
Q
Lymph nodes/glands locations
A
At intervals along the lymphatic vessels
mostly on neck, armpits, groin and around alimentary canal
7
Q
Lymph nodes structure
A
- bean-shapped
- 1-25mm
- surrounded by capsule of connective tissue to form a framework
8
Q
Framework of lymph nodes
5
A
- lymphoid tissue
- masses of lymphocytes (WBC)
- macrophages (WBC)
- plasma cells
- space between has meshwork of fibres
9
Q
How does lymph travel in lymph nodes
A
- enter through fibres of convex side of node
- filters through space
- pass out through vessels on opposite side
10
Q
What can lymph contain that may be dangerous to body
A
- cell-debris
- foreign particles
- micro-organisms
11
Q
How does the lymph system protect body against diseases
A
- larger particles such as bacteria are trapped in meshwork of fibres
- macrophages destroy these particles through phagocytosis (destroyed by enzymes)
- during infection, formation of lymphocytes increase, causing lymph nodes to swell
