Third Line of Defense Immune Response Specific Defense

Third Line of Defense Immune Response (Specific Defense)

Immune Response (Specific Defense) A series of specific defenses that attack a particular disease-causing agent is called an Immune Response

Two Divisions of the Immune System Humoral Immunity Antibodies mark infected cells for death Cell-mediated Immunity Cells attack infected cells

Cells of the Immune System Two types of cells recognize specific B Lymphocytes and T Lymphocytes antigens: B-Cell T-Cell

Antigen A substance on the surface of a pathogen that triggers an immune response is called an Antigen (Germ’s fingerprint)

Antibodies are proteins that recognize and bind to antigens

Plasma Cells • Plasma cells produce antibodies • Antibodies circulate in the bloodstream

Antigen Binding Site Antigen-Binding Sites The site that the antibody binds to the antigen is called the antigen-binding site

Memory Cells Memory cells - are antibody factories preprogrammed to respond to a returning antigen (i. e. vaccination)

You. Tube Cell-Mediated Immunity

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Humoral Immunity Plasma Cell Antibodies B-Cell Pathogens (Bacteria, Virus, Fungi, Worms, Foreign Proteins) 1. Pathogen invades the body 2. B-cell recognizes antigen on pathogen 3. B-cells become Plasma cells, which produce antibodies against the antigen Antibodies bound to pathogen 4. Antibodies bind to the pathogen, marking it for death

Humoral Immunity B-Cells - provides immunity against pathogens found in body fluids.