1. Consists of organs, ducts, and nodes. The Lymphatic System

2. Main Functions: 1.Carries fluids lost from blood back to the circulatory system 2.Defend the body against disease by producing lymphocytes (WBC’s) 3.Absorbs lipids from the intestine and transport them to the blood

3. Lymph 1. Lymph: a clear fluid found in lymph vessels. 2. This fluid first leaked out of the blood vessels that brought O 2 and nutrients to the tissues. Fast Fact: blood loses ~ 4 L of fluid into interstitial fluid each day!

4. Lymph Vessel 1.The lymph vessels run along side veins collecting and carrying lymph back to the circulatory system. 2.Lymph is returned to the circulatory system through veins. 3.Lymph vessels contain valves just like veins; prevents backward flow of lymph Artery - RED Vein - BLUE Lymph Vessel - GREEN

5. Lymph Nodes 1.Lymph nodes are small bean shaped structures (containing white blood cells) found along lymph vessels. 2.They filter pathogens out of the lymph. Lymph nodes are divided into compartments called lymph nodules. The lymph nodules are dense masses of lymphocytes and macrophages and are separated by spaces called lymph sinuses. There are more afferent vessels than efferent vessels. This slows the passage of lymph through the sinuses, which allow time for the lymph nodes to filter the lymph. Lymph nodes are usually less than 2.5 cm long.

6. Tonsils 1.Pair of enlarged lymph nodes in throat. 2.The tonsils trap bacteria and viruses entering through the throat and produce antibodies to help fight infections. 3.Not as helpful in fighting modern infections as in fighting worms or other parasites.

7. Spleen 1.Serves as a reservoir for blood in case of emergencies 2.Filters worn-out red and white blood cells, and platelets from the blood. 3.Stores platelets 4.Contains white blood cells that remove pathogens from blood. The spleen has a spongy consistency and can hold up to 3 gallons of blood.

8. Thymus 1.Located beneath the sternum 2.T cells mature here before they can function in the immune system. 3.It is larger in younger children.

9. Location of Parts Tonsils Thymus Spleen Lymph Vessel Lymph Node

10. http://www.mayoclinic.com/health/cancer/MM00638 The lymphatic system can spread cancer cells that started out as skin cancer. Cancer