Immune System

31.1 Infectious Diseases: Define: –Pathogen-disease causing organisms Ex: bacteria, virus, protozoa, fungi, worms –Infectious disease-diseases caused by pathogens List Methods of Transmission: physical contact, airborne, contaminated food/water, sexual contact, and/or animals What is the Germ Theory of Disease? -infectious disease is caused by pathogens that can spread the disease from one organism to another

31.2 Human Defenses: 2 nd LOD : Internal nonspecific Defenses White Blood Cells –Flows through blood stream –Some eat the pathogens, and when they are inside, white blood cells use an enzyme to kill it –Others poke holes in the infected cells’ membranes, killing the cells Inflammatory Response –When a barrier is broken, a mast cell releases histamine –Histamine causes nearby blood vessels to expand allowing more blood to go to the area –This is why a mosquito bite swells Specialized proteins- they’re like special ops –Interferon's are proteins that stop the viruses form reproducing. Often a cell is infected, produces an interferon, and dies, but passes it on to nearby healthy cells. Useful against common flu’s. 1 st LOD: physical and chemical barriers Called nonspecific defense Traps most of the invaders Examples are sweat glands, skin, hair, mucus membranes, saliva, and tears When trapped in mucus, pathogens can be swallowed and destroyed through digestion 3 rd LOD: Targeted Defense The actual immune system Can recognize and destroy specific pathogens

31.3 immune system Immunity- your body is resistant to the pathogen that causes a specific disease Antigens- a large molecule that provokes an immune response Antibodies- proteins found on the surface of white blood cells that attach to particular antigens

Recognizing the “invaders’ (31.3) The most common antibodies are Y-shaped molecules. At the tip of each arm of the Y is an antigen-binding site. The shape of this binding site makes it possible for the antibody to recognize a specific antigen with a complementary shape. There is a huge variety of 3D shapes of antigen-binding sites. This variety gives antibodies the ability to recognize an equally large variety of antigens.

31.4 Vaccines Vocab: – Vaccines: A dose of a pathogen or part of a pathogen that has been disabled or destroyed so it is no longer harmful – Active Immunity- When the body produces antibodies against an infection – Passive Immunity- When your body receives antibodies from an outside source Process of Vaccination: A harmless dose of a pathogen is injected into the patient so that the body can develop an immunity.

31.5 Disorders of the I.Sys. –Allergies-An allergy is an abnormal over-sensitivity to an otherwise non-harmful antigen, called an allergen. Symptoms include runny nose, watery eyes and sneezing –Autoimmune Disease - In some individuals, the immune system cannot always distiguish between self and non-self. In such cases, the immune system turns against some of the body's own molecules, resulting in an autoimmune disease. Examples of autoimmune diseases include lupus, rheumatoid arthritis, and multiple sclerosis. –Aids/HIV-AIDS stands for acquired immune deficiency syndrome. A virus called HIV, or human immunodeficiency virus, causes AIDS. More than 40 million people are now infected with the AIDS virus, HIV. HIV is deadly because it destroys the immune system, leaving the body unable to defend itself against pathogens and certain cancers. HIV infects a variety of immune system cells, especially helper T cells. When HIV destroys the body's helper T cells, the immune system cannot activate other T cells or B cells. Death usually occurs from another infection, such as pneumonia, or from certain types of cancer.

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Current event on the Swine Flu It is different from the normal flu because it originates from different sources and the symptoms are more severe. It is dangerous because we do no not have a cure for it yet. It compares to the historical flu pandemic a lot. It is a lot like it but more severe.

10 study questions for the Immune System: What is the germ theory of disease? What is one way that infectious diseases are spread? Name the three lines of defense your body has. What is an autoimmune disease? What is a vaccine? What is Humoral immunity? What is cell-mediated immunity? What is active immunity? What is passive immunity? Name one autoimmune disease.

Answers States that infectious disease is caused by pathogens that can spread the disease from one organism to another organism. Spread when pathogens in the air are inhaled. Other diseases are spread by contact. Skin, white blood cells, inflammatory response, and specialized proteins, the immune system A condition in which the immune system attacks some of the body’s own molecules. A dose of a pathogen or part of a pathogen that has been disabled or destroyed so it is no longer harmful. Specific immunity provided by B cells that produce antibodies that circulate in body fluids It involves T cells attacking body cells that are infected with a pathogen. The body produces antibodies against infection. The body receives antibodies for a particular disease from another source. HIV/AIDs