1. Chapter 12 Lymphatic System and Body Defenses

2. 2 parts Network of Lymphatic Vessels Lymphoid Tissues and Organs 3. Lymphatic vessels Flow toward heart Pick up excess tissue fluid and return it to blood Extremely permeable Lymph goes from lymph capillaries to lymphatic collecting vessels Right lymphatic duct drains right arm, right side of head, and thorax Thoracic duct receives the rest of bodys lymph 4. Lymph nodes Remove foreign material from lymphatic stream and produce lymphocytes Cluster 5. Other Lymphoid organs Spleen Thymus Tonsils Peyers patches 6. 2 forms of body defense Innate Adaptive 7. First line of Defense Surface Membrane: barrier for pathogens Produces protective secretions Second line in Defense Cells and Chemicals: phagocytes, natural killer cells, inflammatory cells, and chemical substances 8. Natural killers Lymphocytes Kill cancer cells and other nonspecific targets Act spontaneously 9. Inflammatory response Nonspecific response thats triggered Process Neutrophils enter blood Move through capillary walls to worst area Neutrophils gather and remove foreign material 10. Phagocytes Macrophage or neutrophil Lysosome fuses with phagocytes and digest pathogens Eat away foreign material 11. Antimicrobial Proteins Complement Plasma protein Proteins bind to foreign material Enhance inflammatory and immune responses and phagocyes Interon Proteins Interfere with viruses being able to multiply 12. Fever Increases metabolism Causes liver and spleen to store ion and zinc 13. Adaptive body defenses Immune system: response to threats Third line of defense Two parts Humoral immunity Cellular immunity Three most important parts Antigen specific Systemic Memory 14. antigens Substance initiates our immune system Large complex molecules Strongest are proteins Provoke an immune response then bind with proteins Incomplete antigens cant provoke a response unless it binds with other protein 15. Cells of adaptive defense system Two Parts: Lymphocytes and Antigen- Presenting Cells (APCs) 16. Lymphocytes Develop in red bone marrow Becoming B or T cells depend on immunocompetent T cells oversee cell-mediated immunity B cells provide humoral immunity 17. Anti-presenting cells Present antigens to cells Develop from monocytes Called dendrites or macrophages Live in lymphoid organs 18. Humoral immune response Primary Humoral Response Antigens bind to receptors Causes multiplication of cells Clump of cells Clone members that become plasma members secrete antibodies Secondary Humoral Response B cells that dont become plasma cells become memory cells In charge of immunological memory Much faster because theyve taken care of the same antigens before 19. Antibodies Made by activated B cells or plasma-cell offspring Bind with specific antigens 5 major classes: IgM IgA IgD IgG IgE 20. Antibody Structure Four amino acid chains Two identical heavy and two identical light T or Y shaped Variable region at one end and constant region at the other Variable region forms an antigen-binding site Constant region determine antibody function and class 21. Antibody function Functions: complement fixation, neutralization, precipitation, and agglutination Complement: binds to antibodies attached to cellular targets and triggers lysis Neutralization: antibodies bind to specific sites on bacterial exotoxins. block harmful effects Precipitation: antigens cross-link involve soluble molecules Agglutination: cross-link involves cell-bound antigens and causes clumping 22. CELLULAR (CELL-MEDIATED) IMMUNE RESPONSE T cells must be activated by binding with antigens that macrophages present it to T cells are differentiated to effector T cells and memory T cells Cytotoxix T cells: kill virus-infected, cancer, or foreign graft cells Helper T cells: managers/directors Regulatory T cells: stop immune response when finished 23. Development Lymphatic vessels break off from veins Immune response develops around birth Ability of cells to recognize foreign antigens is genetically determined 24. Diseases 1. Anaphylactic Shock Allergic response Allergens directly enter blood Immunoglobin has an exaggerated response Symptoms: swelling, low blood pressure, hives, and dilated blood vessels Epinephrine needs to be injected to thigh 2. Rheumatoid Arthritis Inflammatory disorder Affects small joins in hands and feet Causes painful swelling Immune system accidently attacks your own body and tissue No cure Medications can reduce pain 25. Technologies 1.Xenographs Transfer of living cells, tissues, or organs from one species to another Used for cancer treatments fatal diseases, and prolong life 26. 2. Lymphoscintigraphy Image technology Radioactive substance flows through lymp ducts and lymph nodes Scanner or probe follow substance on a computer screen Finds sentinel lymph node