Immune System “The defenders” Pg. 40 Ch. 40

Parts of the Immune System

Lymphatic System Stores, circulates & produces WBC. Tonsils- filter & destroy bacteria while lymph is returned via ducts. Thymus- secretes a hormone that helps the WBC mature. Spleen- filters dead red blood cells

ENEMIES & INVADERS Pathogen: any disease causing organism Fungus Athlete’s foot Ringworm Bacteria Diphtheria Staph Virus HIV Influenza Protist Giardia Dysentery

First Line of Defense: Non-specific Defenses: Skin, Mucus, Cilia Wound Phagocytes move into the area and engulf the bacteria and cell debris Bacteria enter the wound Capillary

Non-Specific Defenses: Phagocytes Platelets Histamines = chemical produced during allergic reactions Inflammatory Response = red and itchy

Inflammatory Response: redness& swelling histamine

THIRD LINE OF DEFENSE Immune response: Lymphocytes Phagocytes antigens (invader) antibodies (fighter proteins) Lymphocytes B Cells-produce antibodies T Cells- recognize & destroy invaders Phagocytes consume pathogens

What triggers an immune response? Pathogens Pollen Pet Dander Foods (peanuts) Anything which triggers a response

What are antibodies? Y shaped proteins that bind with specific antigens Once your body makes an antibody for a specific antigen it keeps a memory of it forever (vaccine)

Antibody Binding sites (antigen specific) Antigens

How it works… Antigen enters body Immune system identifies antigen Plasma cells make antibodies Antibodies mark all infected cells Macrophages, T Killer cells destroy infected cells A memory is stored of the antigen for future infections

Primary and Secondary Response Interval between exposures Antibody Concentration First exposure (flu vaccine) Second exposure (exposed to virus) Time

Disorders of Immune System Allergies – (cats, pollen, sea food) Autoimmune- body recognizes itself as foreign and attacks itself Examples: lupus, arthritis, grave’s disease Immunodeficiency Syndromes Body lacks immune cells, can be genetic Acquired Immune Deficiency Syndrome (AIDS) caused by HIV virus, virus attacks and Killer Helper T cells

So how can you boost your immune system? Vaccinations Diet, exercise, rest Cleanliness -self -environment Responsibility -Avoid illegal drugs -Sexual abstinence