The Immune System Topic 14

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1st Line of Defense Chemical & Physical Barriers http://health.allrefer.com/pictures-images/skin-layers.html http://www.nlm.nih.gov/medlineplus/ency/imagepages/19378.htm http://www.webmd.com/digestive-disorders/picture-of-the-stomach

Pathogens are blocked Skin prevents pathogen from entering The nasal passages trap pathogens with hair and mucous. The stomach acid has a pH of about 2. This is too acidic for many pathogens and will prevent them from functioning.

2nd Line of Defense Inflammatory Response The damaged area swells due to white blood cells, called phagocytes, responding to the site of infection. Temperature rises in order to denature proteins in the pathogens, and prevent infection.

Pathogen- anything which can cause an infection (bacteria, virus, fungus, protists) Antigen- Identifying proteins found on a pathogen. Each pathogen has a unique antigen! Antibody- Specialized protein which binds to a specific antigen identifying it for destruction.

3rd Line of Defense Immune Response

2 Types of Lymphocytes T cells- Identify the pathogen each T cell recognizes a specific antigen. http://www.topnews.in/health/diseases/hiv-aids?page=3

2 Types of Lymphocytes B Cells- Produce Plasma cells and Memory cells Plasma cells produce Antibodies Memory cells remember the antigen and matching antibody. http://www.sciencedaily.com/releases/2006/09/060920191637.htm

Immune Response http://go.hrw.com/resources/go_sc/interactOnline/hx/hximn2_io.swf

Immune System Defender Game: http://nobelprize

Immunity Active Immunity- The body produces its own antibodies after having an encounter with a specific pathogen. Passive Immunity- Temporary immunity, antibodies are passed into the body from another source.

Vaccines Vaccine- A dead or weakened pathogen introduced to the body. This allows the body to produce antibodies for that pathogen.

Interactive Making Vaccines: http://www. pbs

Immune System Disorders Allergies- immune system over reacts to an allergen. Histamine is released- triggers an inflammatory response.

Immune System Disorders Asthma- inflammation of the respiratory tract.

Immune System Disorders Autoimmune Disease- immune system does not distinguish between self and non-self. Rheumatoid Arthritis Multiple Sclerosis Diabetes

HIV & AIDS HIV- attacks the T cells Weakens the immune system, leads to development of AIDS

http://www.umm.edu/patiented/articles/what_effects_of_exercise_on_diabetes_000029_4.htm http://www.nlm.nih.gov/medlineplus/ency/imagepages/17130.htm