Full Immune System Notes

Disease and Immunity What is Disease? Disease = a lack or disruption of homeostasis. Changes in ph, nutrient levels, temp, b.p., hormone levels, gas levels, inability to remove wastes. Factors that cause disease Inheritance = born with genes for the disease Microorganisms = Pathogens (microorganisms that cause disease) Examples: Bacteria, Fungi, Protists, Viruses, Worms Pollutants = lead, mercury, coal dust, asbestos fibers Organ Malfunction = heart, liver, kidney. Etc. Harmful life styles = tobacco, alcohol, drugs, overeating, no exercise, unsafe sex, prolonged anger or anxiety Infectious vs. Noninfectious Diseases Infectious = passed from person to person (contagious) Examples: Strep. Throat, Flu, HIV, Mono Noninfectious = not contagious Examples: MS, High Blood Pressure, Cancer How can pathogens enter the body? Bodily fluids contact ( skin, respiratory system, urinary system, mouth and digestive system, reproductive system. How does the body protect itself from disease? Physical & Chemical barriers – 1st Line of Defense Cilia, stomach acid, skin, tears, mucus, sweat, urine, membranes Protect by covering, catching, washing away and destroying pathogens. Inflammatory Response – 2nd Line of Defense A reaction that causes swelling, redness, warmth, pain and increased blood flood to the area of infection. MACROPHAGES – phagocyte WBC’s that rush to the area to engulf large numbers of bacteria ( causing PUS = mixture of phagocytes, dead cells, bacteria and bodily fluid. Immune System – 3rd Line of Defense RADR – Recognizes, attacks, destroys, and remembers each kind of pathogen or foreign substance that enters the body. Pathogen vs. Antigen – How are they similar yet different? Pathogen = microorganism that causes disease Antigen = surface proteins on any substance that can cause an immune response Similar = both cause an immune response Different = Pathogens are microorganisms (alive) AND antigens are anything that causes an immune response (ex: pollen). White Blood Cells Origin ( Made mainly in the bone marrow but also in the Tonsils, Thymus, and Lymph Nodes Phagocytes & Macrophages = engulf bacteria Lymphocytes = (several types) cells involved in the specific recognition of antigens B Cells Respond by producing antibodies that are specific to an antigen Antibodies = proteins with a specific shape that fits the shape of the antigen/Memory cards Body makes many over a lifetime and they remain to remember the pathogen- B MEMORY CELLS T Cells T- helper cells – assist my mediating info. between the white blood cells. These are infected by HIV. T- killer cells – recognize infected cells and destroy them. Immune Response 1. Antigen gets through the physical barrier 2. Macrophage engulfs the bacteria and displays the antigen on the surface so that the T helper cell can bring information to the B cells and T cells 3. B cells divide – some make antibodies for the plasma and some become memory cells. 4. Antibodies bind with the antigen = Antigen-Antibody complex Immunity = A resistance to disease Active Immunity= when the organism develops immunity (antibodies) from a specific antigen (long term) Vaccines = injections of a weakened or dead form of the disease that allows active immunity to develop w/o getting sick. Passive Immunity = when the antibodies are come from an outside source to fight an antigen (short term) Disorders of the Immune System Allergies = immune response to an antigen that is not usually harmful. Histamines = substance released from cells to induce an inflammatory response. Anti-histamines = block histamines to prevent response. Auto Immune Diseases = immune system of an individual fails to recognize some of the body cells as its ‘self’ and produces antibodies against them. Juvenile Diabetes = destroy insulin cells in pancreas Multiple Sclerosis = destroy fatty covering of nerves Lupus = destroy different parts like kidneys. Organ Rejection AIDS = Acquired Immune Deficiency Syndrome HIV – Human Immunodeficiency Virus Pathogen that infects helper T cells. Viral reproduction destroys T cells and person cannot fight any infections. Transmission = Mainly sexually = sexual contact with exchange of bodily fluids Blood ( Blood = intravenous drug users, blood transfusions before 1985 Infected mother ( child Prevention No risk behavior Cancer – uncontrolled cell growth/division and immune system doesn’t recognize it. Symptoms = may include a tumor (benign or malignant) Causes = Viruses Chemicals Tobacco Radiation X-Rays Sunlight (UV) Nuclear Radiation Genetics/Inheritance Increased Risk (Poor Lifestyle Treatments Surgery Drug Therapy Radiation Therapy