The Immune System By Charlotte, Michelle, Sadie, and Tray

Important Terms Pathogens--The "infector" Antigen--A foreign substance that elicits the immune response of recognizing particular microorganisms Antibody--The immune system uses this protein and specialized lymphocytes when responding to an antigen

I. The Three Lines of Defense (5) 1.Barriers at the body's surface 2.Nonspecific Responses 3.Immune Responses

THE FIRST LINE OF DEFENSE: The Barriers at the Body's Surface (5) Attacks Everything Intact skin o For example: oil and sweat secreted from glands give the skin a pH of around 3-5 which is not an ideal place for microorganisms to colonize. Mucous Membrane o For example: nose, eyes, mouth, lysozyme, throat  Lysozyme = An enzyme that digests the cell walls of bacteria, further destroying the risk of infection of the respiratory system and openings around the eyes  In the nose and throat there is mucous that catches microbes.  **The not as strong pathogens get stuck here and are flushed out through tears, saliva, urination, and diarrhea** Infection fighting chemicals o For example: tears, saliva

THE SECOND LINE OF DEFENSE: Nonspecific Responses (5) Attacks Everything Inflammation o Is triggered by physical injury.  Histamine and prostaglandins are released as chemical signals  Blood flow is increased (vasodilation), vessel permeability is increased, and phagocytes migrate to the cut  Phagocytes (macrophages and neutrophils) consume the pathogens and cell debris so that everything can heal Organs with pathogen-killing functions o For example: lymph nodes Some cytotoxic cells with a range of targets o For example: NK cells Natural Killer Cells o Goes around killing the body's own infected cells

THE THIRD LINE OF DEFENSE: Immune Responses (5) Attacks One Thing The immune system is able to recognize invaders by their antigenic markers, and therefore has a memory called acquired immunity T and B cells o Which function in the cell-mediated immune response and carry out humoral immune responses  Humoral Immune Responses are triggered by antibodies Macrophages that interact with the T and B cells Communication signals o For example: interleukins  Interleukin is a chemical regulator that is secreted by the macrophages. It consumes a pathogen and then binds to a T cell. The T cell then grows and multiplies and elevates the body temperature. Chemical Weapons o For example: antibodies o REVIEW:

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II. How Do White Blood Cells Destroy Pathogens in the Blood Stream? -Neutrophil (WBC) divide and are dumped into blood stream and lymph fluids to fight the infection -They fight invaders by "eating" bacteria and other foreign matter, neutrophil membrane wraps around the invader and traps it -T Type lymphocyte kills foreign cells or helps to kill them by releasing chemicals---> endocytosis

III. Vaccines When the body is under attack white blood cells are activated and begin making antibodies Antibodies: Vaccines are made up of a weaker version of the bacteria or virus or a dead form of the organism When injected, antibodies are produced, and after stay in the body, thus when the real disease comes the body is ready to attack it right away Analogy: "most wanted poster" vs. actual killer

III. Active and Passive Immunity! Active Immunity: Naturally acquired: when a person is exposed to a live pathogen by environment Artificially acquired: when a person is exposed to the pathogen through a vaccine Passive Immunity: Naturally acquired: happens during pregnancy, where certain antibodies are passed from the maternal bloodstream into the fetal bloodstream.

IV. Autoimmune Diseases An autoimmune disease is when the immune system attacks and destroys its own tissues. The immune system can't recognize the difference between healthy body tissues and antigens Examples: -Celiac Disease -Type 1 Diabetes -Lupus

Football Analogy Offensive Line- doesn't let other team get near quarterback (Ist) Running Back- if the other team gets past offensive line, then running backs step up to protect quarterback (2nd) Quarterback-up to quarterback to run away from defense or pass the ball to a teammate (3rd)

Bibliography 1. Soni, Rajinder. "Food-How to Keep Yourself Healthy with Probiotics?" Boddunan.com. Boddunan, 15 Sept Web. 23 Oct "Autoimmune Disorders." Lab Tests Online: Welcome! AACC, 13 Oct Web. 24 Oct "Human Physiology/The Immune System - Wikibooks, Open Books for an Open World." Wikibooks. 15 Oct Web. 24 Oct "White Blood Cells." Partnerships for Environmental Education and Rural Health (PEER). Web. 24 Oct Starr, Cecie, Ralph Taggart, and Lisa Starr. "Immunity." Biology the Unity and Diversity of Life. Australia: Brooks/Cole, Print.

Bibliography (cont.) 6. "Inflammatory Response | Biology." Khan Academy. BY-NC-SA. Web. 24 Oct "Immunity: Active and Passive Immunity — Infoplease.com." Infoplease: Encyclopedia, Almanac, Atlas, Biographies, Dictionary, Thesaurus. Free Online Reference, Research & Homework Help. — Infoplease.com. Pearson Education, Web. 24 Oct "How Do Vaccines Work?" HealthyChildren.org - How Do Vaccines Work? American Academy of Pediatrics, 31 May Web. 24 Oct