1. Lymphatic System and Immunity

2. Extracellular Fluid Liquid that surrounds cells
-Capillaries leak water and other
substances from blood plasma through pores (tiny holes).
(3 L /day)
- Diapedesis: when WBC’s alter shape and squeeze through pores

4. Extracellular liquid

5. Lymph
- fluid derived from extracellular fluid as it circulates in the lymphatic vessels to evacuate cell waste

6. Lymphatic System Waste expelled into the extracellular fluid
Lymphatic system returns it to the blood
Transports waste to various organs for elimination
Lymphatic vessels transport LYMPH to the blood (not closed!)

7. Circulation Not the heart like blood circulation
Muscles contracting on the lymphatic vessels (large vessels have valves !)

9. Lymphatic Circulation

10. Defence of our Bodies
Viruses and bacteria usually found in extracellular fluid, lymph, and blood
( contain WBC’s)

11. Lymph nodes & Lymphatic Organs
Lymph circulates in body, travelling through lymph nodes
Lymph Nodes
- small bumps in neck, armpits, and groin
- filter lymph, high concentration of WBC’s, battleground against infection (tonsillitis, flu, etc.)

13. WBC’s act in two ways
Phagocytosis: when WBC’s ingest and destroy certain microorganisms(invaders)

17. 2. Action of Antibodies
-Secreting antibodies which neutralize invaders 1. Antibodies recognize antigens (attached to invader) 2. - Antibodies attach to antigen - now neutralized –prevented from reproducing and attacking 3. Invader eliminated

18. Antibodies and Antigens
-substance secreted by white blood cells to neutralize invaders
- SPECIFIC to one antigen
- Immunizing- WBC’s remember how to produce a particular antibody
Antigen:
- Substance recognized as foreign by the body and that triggers the body’s white blood cells to produce antibodies
Ex. Viruses
Bacteria