Nonspecific defenses

1. Non-Specific Defense (pg 6)

2. Non-Specific Defense (pg 6) Non-specific defenses are directed against all pathogens, regardless of their nature

3. 1 st Line of Defense Physical Barriers: Skin: Cells are tightly packed and contain the tough protein keratin, which makes it difficult for pathogens to penetrate.

4. 1 st Line of Defense Physical Barriers: Skin: Cells are tightly packed and contain the tough protein keratin, which makes it difficult for pathogens to penetrate. Mucous membranes: Line respiratory and digestive tracts.

5. 1 st Line of Defense Physical Barriers: Skin: Cells are tightly packed and contain the tough protein keratin, which makes it difficult for pathogens to penetrate. Mucous membranes: Line respiratory and digestive tracts. Fluids: Tears, saliva, urine: flush pathogens out of the body

6. 1 st Line of Defense Protective Secretions: Skin secretions are acidic and sebum contains chemicals that inhibit bacterial growth

7. 1 st Line of Defense Protective Secretions: Skin secretions are acidic and sebum contains chemicals that inhibit bacterial growth Stomach produces hydrochloric acid, which kills pathogens

8. 1 st Line of Defense Protective Secretions: Skin secretions are acidic and sebum contains chemicals that inhibit bacterial growth Stomach produces hydrochloric acid, which kills pathogens Saliva and tears contain lysozyme , an enzyme that destroys bacteria

9. 1 st Line of Defense Protective Secretions: Skin secretions are acidic and sebum contains chemicals that inhibit bacterial growth Stomach produces hydrochloric acid, which kills pathogens Saliva and tears contain lysozyme , an enzyme that destroys bacteria Mucus traps microorganisms

10. 2 nd Line of Defense Chemical Action Complement: group of proteins that are activated by contact with foreign substances. Activated complement proteins enhance phagocytosis and inflammation and cause bacterial cells to rupture

11. 2 nd Line of Defense Chemical Action Complement: group of proteins that are activated by contact with foreign substances. Activated complement proteins enhance phagocytosis and inflammation and cause bacterial cells to rupture Interferon: Produced by virus-infected cells. Stimulates neighboring cells to block their virus receptors so they don’t get infected

12. 2 nd Line of Defense Phagocytes Neutrophils : First to arrive at site of infection. Engulf a few bacteria and then die. “Suicide mission”. Pus = dead neutrophils

13. 2 nd Line of Defense Phagocytes Neutrophils : First to arrive at site of infection. Engulf a few bacteria and then die. “Suicide mission”. Pus = dead neutrophils Macrophages: Large cells. Arrive later and clean up dead neutrophils and any remaining bacteria. “Clean up crew”

14. 2 nd Line of Defense Phagocytes Neutrophils : First to arrive at site of infection. Engulf a few bacteria and then die. “Suicide mission”. Pus = dead neutrophils Macrophages: Large cells. Arrive later and clean up dead neutrophils and any remaining bacteria. “Clean up crew” Natural Killer Cells: Type of lymphocyte that kills cancer cells and virus-infected cells.

15. 2 nd Line of Defense Fever Macrophages release pyrogens , which cause the hypothalamus to increase body temperature

16. 2 nd Line of Defense Fever Macrophages release pyrogens , which cause the hypothalamus to increase body temperature High fevers are dangerous, but mild fevers are beneficial because they decrease availability of iron and zinc (which slows bacterial growth) and increase metabolic rate (which allows body cells to heal faster).

17. 2 nd Line of Defense Inflammation Occurs in response to tissue damage

18. 2 nd Line of Defense Inflammation Occurs in response to tissue damage Signs = redness, heat, swelling, and pain

19. 2 nd Line of Defense Inflammation Occurs in response to tissue damage Signs = redness, heat, swelling, and pain Increases blood flow to the damaged area, which brings white blood cells and clotting proteins.

20. 2 nd Line of Defense Inflammation Occurs in response to tissue damage Signs = redness, heat, swelling, and pain Increases blood flow to the damaged area, which brings white blood cells and clotting proteins. Inflammation is only helpful when it is temporary and localized. Chronic or systemic inflammation is damaging and dangerous. Symptoms: High white blood cell count, fever, decreased blood pressure (caused by vasodilation )

21. Diagram (pg 7) Steps of inflammatory process

22. Output (pg 7) Choose one type of non-specific defense Write the summary of a movie plot about this process At least 5 sentences