1. By Ian Paris and Ashley Lawson

2. Three main purposes provided by system: 1. Fluid and protein balance: Collects fluid and returns it to circulatory system 2. Immunity and spread of infection: It is the first line of defense again disease 3. Digestion: Absorbs fat from food in digestion(2)

4.  Main function is to aid in fluid balance.  Lymphatic Vessels keep left over interstitial fluid from building up  The vessels act as drains that collect the excess fluid and return it and lymph to the blood just before it reaches the heart through a lymphatic pump.  If left over fluid is left for even a short amount of time the result can be massive edema or swelling resulting in tissue destruction or death.(2)  The vessels also help with homeostasis  They remove large molecular substances that can’t be absorbed by blood capillaries and return accumulated protein back to blood.  Lymphatic Vessels in the small intestine called lacteals absorb fats and other nutrients(1)

8. Function of Lymph Nodes:  Provides defense against harmful forces by filtration and phagocytosis  Sinus channels in lymph nodes slow lymph flow giving cells time to remove microorganisms and other damaging particles from lymph.(1)

10.  Tonsils are masses of lymphoid tissue located in a protective ring under mucous membranes in mouth and back of throat.  Function of tonsils: Help protect against bacteria invading tissue in area around openings between oral and nasal cavities.  Serves as first line of defense from exterior infection and disease.  Main job is to keep pathogens from ever getting into our body through our mouth or nose. (1)

11.  Thymus is an unpaired organ consisting of two pyramid-shaped lobes.  Function of Thymus: Is final site of lymphocyte development before birth.  Soon after birth the thymus starts secreting a group of hormones called thymosin that enable lymphocytes to develop into mature T-cells.  T-cells are just lymphocyte cells produced by thymus gland that participate in immune response.(3)

12.  The spleen is located under the diaphragm  Functions of Spleen:  Defense: macrophages remove microorganisms from blood and destroy them through phagocytosis.  Hematopoiesis: monocytes and lymphocytes complete development and become active in spleen  Before birth red blood cells are developed in spleen.  Red blood cell and platelet destruction: macrophages remove worn-out red blood cells and defective platelets from blood and destroy them through phagocytosis.  Iron and globin are taken from destroyed red blood cells and returned to blood stream for storage in bone marrow and liver.  Blood Reservoir: Blood is stored in pulp of spleen in case of hemorrhage.

14. General: It doesn’t attack anything specific Example: skin blocks everything that is trying to enter the body. Response: If bacteria does enter the body then damaged cells signal for increased blood flow. This increases body temperature that creates an unfavorable environment and delivers T- cells which are supposed to get rid of damaged cells and dead bacteria. (1) Specific: Attacks specific types of infections Example: Vaccination that forms antibodies that create an immunity to the infection. Response: Antibodies are created and delivered to infected areas to destroy a specific type of infection.(1)

15.  Active: A person develops a disease and acquires an immunity to it.(ex. measles as a child)  Injection of a contributing agent results in immunity. (ex. vaccination for polio)  Passive: Baby receives protection from mother through placenta in womb or an infant receives protection from disease causing agents from mother’s milk.  Injection of antibodies that were developed by someone else's immune system.

16. 1. http://www.cayuga- cc.edu/people/web_pages/greer/biol204/ly mphatic1/lymphatic1.htm http://www.cayuga- cc.edu/people/web_pages/greer/biol204/ly mphatic1/lymphatic1.htm 2. http://www.lymphaticresearch.org/main.ph p?menu=about&content=lymphsys http://www.lymphaticresearch.org/main.ph p?menu=about&content=lymphsys 3. http://www.google.com/#hl=en&biw=1260& bih=574&q=T+cell&tbs=dfn:1&tbo=u&sa=X& ei=5ovMTayyCs_ogQeGz_DgBA&ved=0CCQ QkQ4&bav=on.2,or.r_gc.r_pw.&fp=9de76c24b 15c82b4 http://www.google.com/#hl=en&biw=1260& bih=574&q=T+cell&tbs=dfn:1&tbo=u&sa=X& ei=5ovMTayyCs_ogQeGz_DgBA&ved=0CCQ QkQ4&bav=on.2,or.r_gc.r_pw.&fp=9de76c24b 15c82b4