BELL WORK :

1. BELL WORK: • Take out your homework so I can check it. • Turn in your Organ Trail Project (poster AND packet!!) • Turn in your vocabulary project if you didn’t turn it in yesterday!! • Get ready for your homework quiz!

2. CO: I will describe the interactions between the immune and integumentary systems. LO: I will write notes. I will draw and write how the immune system works.

3. Why do we have an immune system? • Attack from outside • animals must defend themselves against invaders (pathogens) • viruses • HIV, flu, cold, measles, chicken pox • bacteria • pneumonia, meningitis, tuberculosisLyme disease • fungi • yeast (“Athlete’s foot”…) • protists • amoeba, malaria • Attack from inside • cancers = abnormal body cells Mmmmm, What’s in your lunchbox?

4. How do you think pathogens can enter the body??

5. Avenues of pathogen attack • Possible points of entry • digestive system • respiratory system • Genitals • Urinary tract • break in skin

6. So, how does your body protect itself from pathogens?

7. Lines of defense • 1st line: Non-specific barriers • broad, external defense • “walls & moats” • skin & mucous membranes • 2nd line: Non-specific patrols • broad, internal defense • “patrolling soldiers” • leukocytes = phagocytic WBC • 3rd line: True immune system • specific, acquired immunity • “elite trained units” • lymphocytes & antibodies • B cells & T cells Bacteria & insectsinherit resistance. Vertebratesacquire immunity.

8. 1st line:General Defense • Barrier • Skin (Integumentary System) • Traps • mucous membranes, cilia,hair, earwax • Elimination • coughing, sneezing, urination, diarrhea, throwing up • Unfavorable pH • stomach acid, sweat, saliva, urine • Lysozymeenzyme • digests bacterial cell walls • tears, sweat Lining of trachea: ciliated cells & mucus secreting cells

9. Integumentary System: Functions • Protection • First line of defense against • Bacteria • Viruses • Protects underlying structures from • Ultraviolet (UV) radiation • Dehydration • Body temperature regulation • If too hot • Dermal blood vessels dilate • Vessels carry more blood to surface so heat can escape • If too cold • Dermal blood vessels constrict • Prevents heat from escaping

10. Integumentary System: Functions • Vitamin D production • Needed for calcium absorption • Sensation • Sensory receptors (nerves) • Excretion • Small amounts of waste products are lost through perspiration (sweat)

11. 2nd line: Non-specific Responses bacteria • Patrolling cells & proteins • attack pathogens, but don’t “remember” for next time • leukocytes • phagocytic white blood cells • macrophages, neutrophils, natural killer cells • Proteins that destroy cells macrophage yeast

12. 2. Inflammatory response • Damage to tissue triggers local non-specific inflammatory response • release chemical signals • capillaries dilate, becomemore permeable (leaky) • increases temperature • Feveroccurs when local inflammatory response is not enough • High body temperature helps defend body

13. 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)

14. 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 response system • attack invaded cells

15. 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

16. Passive immunity • Obtaining antibodies from another individual • maternal immunity (passed while in the womb or during breastfeeding) • Injection • injection of antibodies • short-term immunity

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

18. 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

19. HIV & AIDS • 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: AcquiredImmunoDeficiency Syndrome • death usually from “opportunistic” infections • pneumonia, cancers HIV infected T cell

20. Immune system malfunctions • Auto-immune diseases • immune system attacks ownmolecules & cells • lupus • antibodies against many molecules released by normal breakdown of cells • rheumatoid arthritis • antibodies causing damage to cartilage & bone • diabetes • beta-islet cells of pancreas attacked & destroyed • multiple sclerosis • T cells attack myelin sheath of brain & spinal cord nerves • Allergies • over-reaction to environmental antigens • allergens = proteins on pollen, dust mites, in animal saliva • stimulates release of histamine

21. The rest of class… • Create an Immune System Comic: • Must have at least 4 boxes in your story • Explain ONE of the levels of defense in the immune system • Use “word bubbles” (like the ones shown) to explain what is happening