The Lymphatic System

Functions of Lymphatic System Drain fluid back into the bloodstream from tissues Filters lymph Filters the blood Fights infections

The Lymphatic System Lymph- clear fluid that circulates around the body tissues Contains high number of white blood cells Includes- lymph nodes, spleen, thymus, tonsils, and adenoids

Lymph Nodes Located in armpits, groin, neck, abdomen, pelvis and chest Filter the lymph as it passes through White blood cells attack any bacteria or viruses

White Blood Cells and Antibodies White blood cells produce antibodies- proteins used by immune system to identify and neutralize foreign invaders Antibodies prevent invaders from entering or damaging cells by binding to them; stimulate removal of invader by other cells; trigger destruction of invader by stimulating immune responses Antibodies specific to antigens

Spleen Filters blood to take out worn out red blood cells- Red blood cells are replaced by new ones made in the bone marrow Filters out bacteria, viruses, and other foreign particles White blood cells in spleen attack bacteria and viruses as they pass through

Thymus Small gland under breastbone Helps produce white blood cells Most active in teenagers and shrinks in adulthood

Tonsils and Adenoids Two glands at back of throat Protects entrance to digestive system and the lungs from bacteria and viruses

Vaccines Immunity booster to a certain virus Can be to prevent or improve the effects of a future infection Can be therapeutic ex. Vaccines against cancer

Types of Vaccines Can be dead or inactivated organisms or purified products of them Containing killed microorganisms Containing live modified organisms Containing inactivated toxic compounds ex. Tetanus fragmented

Developing Immunity Immune system recognizes vaccines as foreign, destroys them, ‘ remembers ’ them Upon entry of virus, immune system recognizes foreign invaders, neutralizing and destroying cells infected by them

Efficacy of Vaccines Vaccines do not guarantee complete protection from a disease Sometimes the immune system does not respond properly or at all ex. low immunity due to diabetes, steroid use, HIV infection

Typical Vaccinations Polio Hepatitis A,B Tetanus Diphtheria Chicken pox