Dispatch

1. Dispatch • Take out April calendar and pick up a book -Today is the review (nut/lunch and afterschool) -This Sat is the AP Exam #1 8-11 or Wed, April 16 3-6 -Today we have reading quiz Chapter 43 2) Share with your tablemates what you did during break. Combine what all members did in one word Example: Magicbeachshopping 3) Study notes chapter 43

2. Ms. Morris went to Zion, Utah

3. Chapter 43 ~ phagocytes • The Body’s Defenses lymphocytes attacking cancer cells

4. Exit Quiz • Explain the inflammatory response • What are the main advantages and disadvantages of a physical barrier against infection? • Sketch a B-cell receptor. Label V + C regions of light and heavy chains. Mark positions of antigen-binding sites, disulfide bridges and transmemebrane regions. • If a child were born without a thymus what cells and functions would be deficient. Explain. • HIV targets include all of the following EXCEPT: A Macrophage B Cytotoxic T-cells C Helper T-cells D Brain cells

5. Exit Quiz Answers 1) The inflammatory response (inflammation) occurs when tissues are injured by bacteria, trauma, toxins, heat, or any other cause. The damaged cells release chemicals including histamine, bradykinin, and prostaglandins. These chemicals cause blood vessels to leak fluid into the tissues, causing swelling. This helps isolate the foreign substance from further contact with body tissues. • The chemicals also attract white blood cells called phagocytes that "eat" microorganisms and dead or damaged cells. This process is called phagocytosis. Phagocytes eventually die. Pus is formed from a collection of dead tissue, dead bacteria, and live and dead phagocytes. 2) What are the main advantages and disadvantages of a physical barrier against infection? A physical barrier often provides a very effective defense against infection. However it is necessarily incomplete because animals need openings in their bodies for exchange with the environment. 3) Sketch a B-cell receptor. Label V + C regions of light and heavy chains. Mark positions of antigen-binding sites, disulfide bridges and transmemebrane regions. 4) If a child were born without a thymus he/she would not have functional T-cells. Without helper T-cells to help activate B-cells, child would be unable to produce antibodies against bacteria. Without T-cells or helper t-cells the child would be unable to kill viruses. 5) HIV targets include all of the following EXCEPT: B Cytotoxic T-cells

6. Lines of Defense Nonspecific Defense Mechanisms……

7. 1st line: Non-specific External defense Lining of trachea: ciliated cells & mucus secreting cells • Barrier • skin • Traps • mucous membranes, cilia,hair, earwax • Elimination • coughing, sneezing, urination, diarrhea • Unfavorable pH • stomach acid, sweat, saliva, urine • Lysozyme enzyme • digests bacterial cell walls • tears, sweat

8. 2nd line: Non-specific patrolling cells bacteria • Patrolling cells & proteins • attack pathogens, but don’t “remember” for next time • leukocytes • phagocytic white blood cells • macrophages, neutrophils, natural killer cells • complement system • proteins that destroy cells • inflammatory response • increase in body temp. • increase capillary permeability • attract macrophages macrophage yeast

9. Leukocytes: Phagocytic WBCs • Attracted by chemical signals released by damaged cells • ingest pathogens • digest in lysosomes • Neutrophils • most abundant WBC (~70%) • ~ 3 day lifespan • Macrophages • “big eater”, long-lived • Natural Killer Cells • destroy virus-infected cells & cancer cells

10. Destroying cells gone bad! • Natural Killer Cells perforate cells • release perforin protein • insert into membrane of target cell • forms pore allowing fluid to flow in & out of cell • cell ruptures (lysis) vesicle natural killer cell perforin cell membrane perforinpuncturescell membrane cell membrane virus-infected cell

11. Anti-microbial proteins • Complement system • ~20 proteins circulating in blood plasma • attack bacterial & fungal cells • form a membrane attack complex • perforate target cell • apoptosis • cell lysis extracellular fluid complement proteinsform cellular lesion plasma membrane of invading microbe complement proteins bacterial cell

12. Inflammatory response • Damage to tissue triggers local non-specific inflammatory response • release chemical signals • histamines & prostaglandins • capillaries dilate, becomemore permeable (leaky) • delivers macrophages, RBCs, platelets, clotting factors • fight pathogens • clot formation • increases temperature • decrease bacterial growth • stimulates phagocytosis • speeds up repair of tissues

13. Fever • When a local response is not enough • system-wide response to infection • activated macrophages release interleukin-1 • triggers hypothalamus in brain to readjust body thermostat to raise body temperature • higher temperature helps defense • inhibits bacterial growth • stimulates phagocytosis • speeds up repair of tissues • causes liver & spleen to store iron, reducing blood iron levels • bacteria need large amounts of iron to grow

14. Dispatch • Draw a label a heart • How is 02 transported to mitochondria? • How is CO2 transported from mitochondria? This Sat in this room. Be here at 7:50 am. Part I 100 multiple choice in 1.5 hours. Part II 4 FRQs If your name is on the board, clear up your N

15. FLT • I can compare the circulatory system and the urinary system with the skeleton baby -Heart -1 Artery along arm -1 Vein along arm -Urinary system (kidney, urethra, ureter, bladder)

16. Immune System Play • While actors are practicing, copy immune chart pg 848

21. After play 1) Fill in the T-chart with 3 or more difference between a bacteria and virus. 2) A B-cell has antibodies. These antibodies are used to______________________ 3) The role of a T-cell is to__________ 4) What is the first line of defense our body has against pathogens?______________ 5) How is a virus attack handled differently than a bacterial attack by the body?_______

22. 3rd line: Acquired (active) Immunity B cell • Specific defense with memory • lymphocytes • B cells • T cells • antibodies • immunoglobulins • Responds to… • antigens • cellular name tags • specific pathogens • specific toxins • abnormal body cells (cancer)

23. How are invaders recognized? • Antigens • cellular name tag proteins • “self” antigens • no response from WBCs • “foreign” antigens • response from WBCs • pathogens: viruses, bacteria, protozoa, parasitic worms, fungi, toxins • non-pathogens: cancer cells, transplanted tissue, pollen “self” “foreign”

24. Lymphocytes bone marrow • B cells • mature in bone marrow • humoral response system • “humors” = body fluids • attack pathogens still circulating in blood & lymph • produce antibodies • T cells • mature in thymus • cellular mediated system • attack invaded cells • “Maturation” • learn to distinguish “self”from “non-self” antigens • if react to “self” antigens, cells are destroyed during maturation

25. B cells • Attack, learn & remember pathogens circulating in blood & lymph • Produce specific antibodiesagainst specific antigen • Types of B cells • plasma cells • immediate production of antibodies • rapid response, short term release • memory cells • continued circulation in body • long term immunity

26. Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Antibodies Y Y Y Y Y Y Y • Proteins that bind to a specific antigen • multi-chain proteins • binding region matches molecular shape of antigens • each antibody is unique & specific • millions of antibodies respond to millions of foreign antigens • tagging “handcuffs” • “this is foreign…gotcha!” Y Y antigen-binding site on antibody Y antigen Y Y Y variable binding region Y Y each B cell has ~50,000 antibodies

27. Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y antigen-binding site variable region s s s s s s s s light chain s s s s s s s s s s s s s s s s heavy chains s s s s light chains s s s s s s s s antigen-binding site antigen-binding site heavy chains Structure of antibodies Y Y Y Y Y Y Y Y Y light chain B cell membrane

28. Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y invader(foreign antigen) B cells + antibodies memory cells “reserves” recognition Y capturedinvaders Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y macrophage Y Y Y Y Y Y Y Y Y Y clones 1000s of clone cells plasma cells release antibodies 10 to 17 days for full response B cell immune response tested by B cells (in blood & lymph)

29. Induction of Immune Responses • Primary immune response:lymphocyte proliferation and differentiation the 1st time the body is exposed to an antigen • Plasma cells: antibody-producing effector B-cells • Secondary immune response: immune response if the individual is exposed to the same antigen at some later time~ Immunological memory

30. Vaccinations • Immune system exposed to harmless version of pathogen • stimulates B cell system to produce antibodies to pathogen • “active immunity” • rapid response on future exposure • creates immunity without getting disease! • Most successful against viruses

31. T What if the attacker gets past the B cells in the blood & actually infects (hides in) some of your cells? You need trained assassins to recognize & kill off these infected cells! Attackof the Killer T cells! But how do T cellsknow someone ishiding in there?

32. MHC protein T or Bcell MHC proteins displaying self-antigens How is any cell tagged with antigens? • Major histocompatibility (MHC) proteins • proteins which constantly carry bits of cellular material from the cytosol to the cell surface • “snapshot” of what is going on inside cell • give the surface of cells a unique label or “fingerprint” Who goes there? self or foreign?

33. MHC proteins displaying foreign antigens TH cell WANTED How do T cells know a cell is infected? • Infected cells digest some pathogens • MHC proteins carry pieces to cell surface • foreign antigens now on cell membrane • called Antigen Presenting Cell (APC) • macrophages can also serve as APC • tested by Helper T cells infectedcell T cell with antigen receptors

34. T cells • Attack, learn & remember pathogens hiding in infected cells • recognize antigen fragments • also defend against “non-self” body cells • cancer & transplant cells • Types of T cells • helper T cells • alerts rest of immune system • killer (cytotoxic) T cells • attack infected body cells • memory T cells • long term immunity T cell attacking cancer cell

35. Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y killerT cell APC:activated macrophage activatekiller T cells stimulateB cells &antibodies APC:infected cell helperT cell helperT cell helperT cell helperT cell helperT cell Y Y Y Y Y Y Y Y T cell response recognition interleukin 2 interleukin 1 or interleukin 2 clones recognition

36. Attack of the Killer T cells • Destroys infected body cells • binds to target cell • secretes perforin protein • punctures cell membrane of infected cell vesicle Killer T cell Killer T cellbinds toinfected cell cell membrane perforinpuncturescell membrane cell membrane infected cell destroyed target cell

37. Abnormal immune function I • Allergies • hypersensitive responses to environmental antigens (allergens); mast cells release histamine causes dilation and blood vessel permeability, epinephrine • Antihistamines can relieve symptoms anaphylactic shock: life threatening reaction to injected or ingested allergens.

38. Abnormal immune function II • Autoimmune disease: • The system turns against the body’s own molecules • Examples: multiple sclerosis, lupus, rheumatoid arthritis, insulin-dependent diabetes mellitus Rheumatoid arthritis

39. Abnormal immune function III • Immunodeficiency disease: • Immune components are lacking, and infections recur • Ex: SCIDS Severe combined immunodeficiency (bubble-boy); A.I.D.S., Acquired Immunodeficency syndrome

40. Abnormal immune function IV • Human Immunodeficiency Virus • virus infects helper T cells • helper T cells don’t activate rest of immune system: killer T cells & B cells • also destroys helper T cells • AIDS: Acquired ImmunoDeficiency Syndrome • infections by opportunistic diseases • death usually from • “opportunistic” infections • pneumonia, cancers HIV infected T cell