By Melanie E. Alexis C. Lavinia G.

General Functions Lymphatic System circulates the lymph fluid throughout the body Immunity= Lymph fluid consisting of antibodies and lymphocytes Fluid and Protein Balance= prevents loss of fluids by collecting it in the lymphatic vessels and returning it to the circulatory system Digestion= help in the absorption of fats from food, prevents obesity Excretion= assists in excretion of waste materials from the body Transportation of nutrients= delivers nutrients in the body through the blood

Major Organs

Skin= forms germ-proof barrier Nose= hairs and mucus trap germs and dirt from air Ears= wax inside traps germs Eyelids= keeps germs out of your eyes Tears= wash eyes clean Stomach= hydrochbris acid kills germs in food Tonsils and Adenoids= kills germs in throat White Blood Cells= destroying germs inside your body Spleen= contains white blood cells which fight infection

Lymph Capillaries Lacteals Lymph Nodes Lymph Vessels Main Lymphatic Ducts

Lymph Node Lymph nodes are small organs found in clusters around the system in your neck, armpits and groin. Make lymphocytes which destroy germs with chemicals called antibodies. Special antibodies attacks specific antigens Are located along lymphatic pathways Filters any possible harmful partials from the lymph before it travels to the blood stream Center for lymphocyte production

The Spleen Produces lymphocytes (type of white blood cells) Red pulp is concerned with filtration activities, removing damaged red blood cells from the body Reservoir of blood Preserves iron and important components from damaged blood cells Stored as bilirubin and ferritin Stores monocytes (helps engulf and digest bacteria and other harmful microorganisms

The Thymus -Most active in youth -Enlarges as you grow older (then recedes at its peak) -Produces hormones that regulate T-cell growth

Immunoglobins (Antibodies) Antibodies attack antigens, help activate proteins to attack or make changes in local areas to protect it from antigens spreading Immunoglobulin A: found in exocrine gland secretions. Breast milk, tears, nasal fluid, gastric juice, intestinal juice, bile and urine Immunoglobulin G: plasma tissue fluids, is particularly effective against bacteria, viruses, and toxins. Actives group of immune system enzymes called complement Immunoglobulin M: type of antibody that develops in the blood plasma in response to contact with certain antigens in food or bacteria. Also activates complement. Immunoglobulin D: found on the surfaces of most B cells, especially those of infants. Also is important in activating B cells. Immunoglobulin E: appears in exocrine secretions along with Lg A. It is associated with allergic reactions.

Primary/Secondary Immune Responses Primary Immune Response= when B or T cells become activated for the first time after which some cells remain as memory cells Secondary Immune Response= when the same antigen is encountered again

Active/Passive Immunity Natural active immunity occurs when is a person is exposed to a live pathogen, develops the disease and becomes immune Artificially acquired active immunity can be gained by a vaccine (a substance that contains the antigen) a vaccine stimulates a primary response against the antigen without causing symptoms of the disease Natural passive immunity occurs during pregnancy, when certain antibodies are passed from the mother to the child through the bloodstream Artificially acquired passive immunity is gained through injection of antibodies

Allergic Reactions Allergic reactions to allergens are excessive immune responses that can lead to tissue damage Mast cells release histamine and leukotrienes, producing a variety of effects Delayed-reaction allergy= results from repeated exposure to substances that cause inflammatory reactions in the skin Immediate-reaction allergy= inherited ability to overproduced IgE

Tissue Rejection Reactions A transplant recipient’s immune system may react with foreign antigens on the surface of the transplanted tissue, causing a tissue rejection reaction Closely matched tissues reduce the chance of tissue rejection, and use of immunosuppressive drugs may reduce rejection, although the individual may be more susceptible to infection

Autoimmunity In autoimmunity disorders, the immune system manufactures antibodies against some of its own antigens Autoimmune disorders may result from viral infection, faulty T cell development, or reaction to a nonself antigen that bears close resemblance to a self antigen

Diseases: HIVs - “Human Immunodeficiency Virus” - Breaks down immune system by infecting immune cells - HIV infects vital cells in the human immune system such as helper T cells (specifically CD4 + T cells), macrophages, and dendritic cells -When CD4 + T cell numbers decline below a critical level, cell-mediated immunity is lost, and the body becomes progressively more susceptible to opportunistic infections.

Diseases: SCID (Severe Combined Immune Deficiency) A genetic disorder identified by the absence of working T-lymphocytes Creates a defective antibody response It is the most severe form of primary immunodeficiencies Its known as the bubble boy disease because the patients are extremely vulnerable to infectious diseases Patients are usually affected by severe bacterial, viral, or fungal infections early on and often present with, chronic diarrhea, interstitial lung disease, and failure to thrive

Scleroderm Is a chronic systemic autoimmune disease derma = skin Limited systemic sclerosis/scleroderma Diffuse systemic sclerosis/scleroderma The cause is unknown affects the small blood vessels in all organs