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50 Cards in this Set
- Front
- Back
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Barriers to Entry
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Skin, Mucous Membranes, Tears, Saliva, Sweat, Oil from Sebaceous Glands, Lysozymes
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Barriers to Entry: Skin
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Keeps most organisms out, many layers of tightly packed cells and some oil producing glands
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Barriers to Entry: Mucous Membranes
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slippery fluids, cillia like in nose that catch bacteria
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Barriers to Entry: Tears
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-tears produce lysosyme (lyses bacteria by degrading bacteria walls)
-tears flush out some contaminates |
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Barriers to Entry: Saliva
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contains acids and enzymes that degrade some enzymes
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Barriers to Entry: Sweat
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sweat glands produce salt that harms some bacteria
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Barriers to Entry: Oil from Sebaceous Glands
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Glands that produce oils that repel some organisms
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Barriers to Entry: Gastric Juices
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acids and enzymes
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Stem cells
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produced by bone marrow differentiate into different cells
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Red Blood Cells - characteristics
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-oxygen containing red blood cells look plump, depleted cells look concave
-red blood cells do not have a nucleus as they do not reproduce |
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Platelets - characteristics
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platelets also produced from stem cells, platelets are non cellular and cause clotting, not part of specific or non specific defenses
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Erythrocytes
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Red Blood Cells (RBCs)
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Leukocytes
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White Blood Cells (WBCs)
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White Blood Cells - characteristics
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-part of non specific defenses
-4 types (in order from largest amount in plasma to smallest): Neutrophils, Monocytes, Eosinophils, Basophils |
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WBC Types: Neutrophils
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-Highly segmented nucleus
-acts as a phagocyte (eats pathogens) (explained on handout) |
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WBC Types: Monocytes
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not usually round in shape, -more intact nucleus
-involved in phagocytoses -become macrophages and ingest pathogens |
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WBC Types: Eosinophils
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-reddish (darker red than red blood cells and larger)
-focus on attacking parasites primarily worm parasites -group attacks on parasites – envelop parasites and isolate them like a plastic bag (suffocate parasites) |
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WBC Types: Basophils
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-one piece nucleus (often bent)
-stain purple -function: allergic reactions -encounter allergens and release histamine granules -often the histamines cause the symptoms |
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Vasodilation
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once you are infected with a pathogen cells release lots of chemicals
Chemicals cause blood vessels to dilate dilated blood cells allow blood and white blood cells to flow freely |
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Inflammation
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Redness, pain, heat, swelling
caused by vasodilation lots of cells in injured area cause inflammation |
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Fever
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Fever is also caused by inflammation
Metabolism rate increases allowing faster response by body Heat may destabilize pathogens by denaturing proteins |
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Complement Proteins
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at least 33 and possibly more types
various functions - info on handout Cell lysis (they can bind to foreign cells and can poke holes in cell walls) Opsonization something binds to cell and marks it as hostile like marking a target with smoke for an air strike Histamines release Basophils and Mast cells have histamines often they don't come into direct contact with pathogen complement proteins bind to Basophils and Mast cells and stimulate histamine release Chemotaxis compliment proteins are more likely to come into contact with pathogens once pathogens are encountered compliment protiens give immune system cells a swift kick in the ass to get them moving by binding to them |
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Soluble Factors
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released by cells of various types
interferon (IFN) antiviral factor released when viruses are detected tumor necrosis factor (TNF) released when tumors are detected and kills off tumor cells interleukins (IL) mostly a specific defense calls in the calvary against pathogens stimulate increased immune response lytic enzymes |
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NK (Natural Killer) Cells
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Mercenary immune cells
independent process from immune system they float around killing anything they don't like on a moments notice |
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Types of Immunity
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Innate/Acquired
Active/Passive Natural/ Artificial |
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Innate vs. Acquired Immunity
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Innate: Genetic Immunity passed down from parents (inborn Factors)
Acquired: Obtained from outside source - exposure to pathogen or gained from mother/mother's milk |
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Acquired Immunity: Active
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Natural:
-Exposed to pathogen, show symptoms, acquire immunity -Immune system becomes acclimated to pathogen via antibodies -antibodies persist in system to prevent disease Artificial: -Vaccination -Exposed to weakened pathogen -Immune system becomes acclimated to pathogen as in natural -you do not become sick but still gain immunity -some people are allergic to vaccines, and rarely vaccines do not trigger immunity -most allergic reactions are to packaging chemicals not pathogen |
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Acquired Immunity: Passive
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Natural:
-Acquire mothers antibodies (some not all) -only acquire a subset of mothers acquired immunities -newborns immune system is weak to begin with and gets mothers antibodies for protection -newborns immunities are not permanent -can also be acquired from mothers milk Artificial ex:Rattlesnake bite in desert -immune system takes a few days to kick in -antiserum is an externally supplied immunity that can be injected to provide immunity venom is injected into horse -Horse antibodies are injected into victim and provide temporary immunity -Horse antibodies are destroyed quickly, immune system targets foreign material |
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Specific Immune Response - characteristics
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Cellular components:
-blood – WBC (White blood cells) -NK (natural killer) Cells Release chemicals that directly kill intruders “mercenary” in that they dont associate with rest of immune system Dendritic cells Unusual looking cells (large surface area to volume ratio – star shaped) specialized Antigen presenting cells they bind to pathogens and present them to immune system (like a pair of handcuffs) Lymphocytes Most important cells of immune response B – Cells Plasma B – Cells T – Cells 2 Branches: Humoral and Cell-Mediated |
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Humoral Immunity: B Cells
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B – Cells (plasma cells, lymphocytes)
-B – Cells do not themselves fight disease -They produce antibodies that work against pathogens |
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Humoral Immunity: Antibodies (Ab)
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Antibodies are fairly large proteins
Have 4 subunits 5 different types Share a typical structure Heavy polypeptide chains Light polypeptide chains Held together by electrical charges and disulfide bridges Y shaped structure 2 heavy chains on inside and 2 light chains on outside there is a Constant region for similar types of antibodies (stem of Y) there is a variable region that is different in every antibody (tips of Y) Variable region is where pathogen binds and determines function Antibodies can bind to immune cells to trigger phagocytosis constant region is region that binds to immune cells (antigen elimination region) variable region is pathogen region (antigen binding region) |
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Clonal Selection Theory
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The clonal selection theory has become a widely accepted model for how the immune system responds to infection and how certain types of B and T lymphocytes are selected for destruction of specific antigens invading the body.
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4 Postulates of Clonal Selection Hypothesis
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1) Each lymphocyte bears a single type of receptor with a unique specificity.
2) Receptor occupation is required for cell activation. 3) The differentiated effector cells derived from an activated lymphocyte will bear receptors of identical specificity as the parental cell. 4) Those lymphocytes bearing receptors for self molecules will be deleted at an early stage. |
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Humoral Immunity: Antibodies:
IgG |
IgG same constant region can bind 2 antigens
Most numerous of antibodies takes over for IgM penetrates entire bodies inter-cellular spaces can cross placental barrier and provides birth immunity |
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Humoral Immunity: Antibodies:
IgD |
IgD same constant region can bind 2 antigens
We don't know what the hell it does or why we have it |
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Humoral Immunity: Antibodies:
IgE |
IgE same constant region can bind 2 antigens
Targets allergens like bee venom |
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Humoral Immunity: Antibodies:
IgA |
IgA two bound antibodies can bind 4 antigens
Found in mucous membranes work against mucous pathogens can be transmitted through mothers milk |
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Humoral Immunity: Antibodies:
IgM |
IgM 5 Bound antibodies can bind 10 antigens
First antibodies to appear (first to disappear) not fast due to size can bind lots of pathogens |
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Once bound, antibodies can...
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Agglutinize, Neutralize, Opsonize, Phagocytose
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Antibodies: Agglutination
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antibodies can bind multiple antigens (2 or more)
Agglutination causes antigens to clump as multiple antigens are chained together and held in place Agglutination prevents antigen movement and holds them in place for disposal by other immune elements |
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Antibodies: Neutralization
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one antibody binds to two antigens preventing them from functioning
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Antibodies: Opsonization
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"tagging" or "labeling"
antibodies bind antigen and calls for backup from immune system |
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Antibodies: Phagocytosis
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antibodies call for immune system cells to devour antigens via phagocytosis
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Humoral Immunity: B Cells, origin
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Cells start out as stem cells
When you need B – cells they are produced in bone marrow and mature in bone marrow Maturation takes several months and adult cells are released into blood |
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Humoral Immunity: Antigen (Ag)
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Antigen (distinctive characteristic of pathogen)
Molecules on surface of Pathogen act as Antigenic Determinants Antibodies bind to matched antigen determinant sites |
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Cell-Mediated Immunity: T Cell Characteristics
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T – Cells attack antigens directly they do not produce antibodies
Cells start out as stem cells but don't stay in bone marrow to mature migrate to thymus gland in upper chest before maturity They finish maturation in Thymus As you get older thymus shrinks and can mature less T – Cells weakening immune system T Cells are identified by type of receptor |
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Cell-Mediated Immunity:
CD4 T-Cells |
regulates the immune system to keep it from overreacting in order to prevent autoimmune and/or inflammatory response
T Helper cells (Th) ambiguous historical definitions release chemicals to stimulate other T Helpers and CD8 to reproduce can stimulate B-Cell production Can stimulate Macrophages (Phagocytes) Macrophages are sedate unless stimulated works in conjunction with humoral branch |
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Cell-Mediated Immunity:
CD8 |
CD8:
azy, stimulated by complement proteins or chemicals released by T helper cells, they consist of T cytotoxic cells (Tc) which can directly release chemicals toxic to the cell when they come into contact with a pathogen or virus that degrade or break it down immediately, and Tc are stimulated to reproduce prolifically T cytotoxic Tc Directly kill pathogens via chemicals cytotoxins T regulatory shut down immune response once pathogen is destroyed tell immune response to back down and prevent it from attacking body |
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What controls unique immune response like variable site on antibodies and T cells?
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your DNA has a section that codes constant region
V,D & J clusters code for variable sites 85 V, 27 D, 6 J genes in clusters like a combination lock 14 V,6D,2J = one active region combinations form wide varieties of variable regions |
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How do Humoral and Cell-Meditated defenses work together?
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4-5 days for active defense to respond to new pathogen
Clonal selection Stem Cells are produced, they begin to differentiate ofer a course of months B and I are called Anti self, they attack your own cells and are usually destroyed prenatally Antiself cells are those which have receptors for your own bodily cells. (Bad) can cause immune disorders first antigens contaminate your body, they encounter a B cell with matching receptors B Cell becomes active due to Antigen and T Helper stimulation, B Cells begin to clone themselves for about 12 generations (exponential growth) some B Cells become Plasma Cells and start pumping out antibodies Plasma B Cells wear out due to extreme activity and die in 2-3 days Cells that don't become plasma B Cells become memory cells Memory B Cells persist to increase response time on future contamination by the same pathogen Memory B cells allow the immune system to generate active response in under 12 hours instead of 4-5 days |
